Guest guest Posted January 25, 2004 Report Share Posted January 25, 2004 Dear As you said " Hi, I'm new................. " *********** You are welcome to join in our debate " I haven't read much of the board yet,........... " READ THIS PLEASE and COMMENT upon the info provided by the DRUG maker respectfully morse Effexor maker (Wyeth) ADMITS to PAEDIATRIC suicidal ideation in it's OWN DATA files http://www.medsafe.govt.nz/profs/Datasheet/e/Efexorxrcap.htm " Paediatric Use Safety and effectiveness in individuals below 18 years of age have not been established. Efexor-XR should not be used in such patients. As with adults, decreased appetite, weight loss, increased blood pressure and increased serum cholesterol have been observed in children and adolescents aged 6 to 17 years. In paediatric clinical trials, there were increased reports of hostility and, especially in major depression, suicide-related adverse events such as suicidal ideation and self-harm.............. " Data Sheet EFEXOR®-XR (Venlafaxine Hydrochloride) Modified Release Capsules NAme of drug EFEXOR-XR Venlafaxine hydrochloride 75 mg and 150 mg modified release capsules. DESCRIPTION EFEXOR-XR capsules are an extended-release formulation, which release the active constituent, venlafaxine hydrochloride, from spheroids within the capsule. Drug release is controlled by diffusion through the coating membrane on the spheroids and is not pH dependent. Two strengths of EFEXOR-XR capsules are available containing either 75 mg or 150 mg of venlafaxine (as hydrochloride). Venlafaxine hydrochloride is chemically defined (R/S)-1-[(2- dimethylamino)-1-(4-methoxyphenyl)ethyl] cyclohexanol hydrochloride. It is a white to off-white crystalline solid with a solubility of 572 mg/mL in water (adjusted to ionic strength of 0.2 M with sodium chloride). Its molecular weight is 313.87. Other ingredients are cellulose-microcrystalline, ethylcellulose, hypromellose, gelatin, red iron oxide CI 77491, yellow iron oxide CI 77492, titanium dioxide and talc purified. PHARMACOLOGY Actions Venlafaxine is a structurally novel antidepressant for oral administration; it is chemically unrelated to tricyclic, tetracyclic, or other available antidepressant agents. The antidepressant action of venlafaxine in humans is believed to be associated with its potentiation of neurotransmitter activity in the central nervous system. Preclinical studies have shown that venlafaxine and its major metabolite, O-desmethylvenlafaxine (ODV), are potent inhibitors of serotonin and noradrenaline reuptake, and also weakly inhibit dopamine reuptake. Venlafaxine is a racemate. The R-enantiomer is relatively more potent than the S-enantiomer with regard to inhibition of noradrenaline reuptake; the S- enantiomer is more potent regarding inhibition of serotonin reuptake. Both enantiomers are more potent on serotonin compared to noradrenaline reuptake. The enantiomers of ODV also inhibit both noradrenaline and serotonin reuptake, with the R-enantiomer being more potent. Venlafaxine and its major metabolite appear to be equipotent with respect to their overall action on neurotransmitter re-uptake and receptor binding. Studies in animals show that tricyclic antidepressants may reduce ß-adrenergic receptor responsiveness following chronic administration. In contrast, venlafaxine and ODV reduce ß-adrenergic responsiveness after both acute (single dose) and chronic administration. Venlafaxine has no significant affinity for rat brain muscarinic, H1- histaminergic or a1-adrenergic receptors in vitro. Pharmacological activity at these receptors is potentially associated with various sedative, cardiovascular, and anticholinergic effects seen with other psychotropic drugs. Venlafaxine does not possess monoamine oxidase (MAO) inhibitory activity. In vitro studies revealed that venlafaxine has virtually no affinity for opiate, benzodiazepine, phencyclidine (PCP), or N-methyl-D- aspartic acid (NMDA) receptors. Venlafaxine also does not produce noradrenaline release from brain slices. It has no significant central nervous system (CNS) stimulant activity in rodents. In primate drug discrimination studies, venlafaxine showed no significant stimulant or depressant abuse liability. Pharmacokinetics Steady-state concentrations of venlafaxine and ODV are attained within 3 days of oral multiple-dose therapy. Venlafaxine and ODV exhibited linear kinetics over the dose range of 75 to 450 mg/day. Mean±SD steady-state plasma clearance of venlafaxine and ODV is 1.3±0.6 and 0.4±0.2 L/h/kg, respectively; apparent elimination half- life is 5±2 and 11±2 hours, respectively; and apparent (steady- state) volume of distribution is 7.5±3.7 and 5.7±1.8 L/kg, respectively. Absorption On the basis of mass balance studies, at least 92% of a single oral dose of venlafaxine is absorbed, indicating that absorption of venlafaxine is nearly complete. However, the presystemic metabolism of venlafaxine (which primarily forms the active metabolite, ODV) reduces the absolute bioavailability of venlafaxine to 42%±15%. After administration of EFEXOR-XR (150 mg q24 hours), the peak plasma concentrations (Cmax) of venlafaxine (150 ng/mL) and ODV (260 ng/mL) were attained within 6.0±1.5 and 8.8±2.2 hours, respectively. The rate of absorption of venlafaxine from the EFEXOR-XR capsule is slower than its rate of elimination. Therefore, the apparent elimination half-life of venlafaxine following administration of EFEXOR-XR (15±6 hours) is actually the absorption half-life instead of the true disposition half-life (5±2 hours) observed following administration of an immediate-release tablet. When equal doses of venlafaxine, administered either as an immediate- release tablet taken in divided doses or as a modified-release capsule, were taken once a day, the exposure (AUC, area under the concentration curve) to both venlafaxine and ODV was similar for the two treatments, and the fluctuation in plasma concentrations was slightly lower following treatment with the EFEXOR-XR capsule. Therefore, the EFEXOR-XR capsule provides a slower rate of absorption, but the same extent of absorption (i.e., AUC), as the venlafaxine immediate-release tablet. No accumulation of venlafaxine or ODV has been observed during chronic administration in healthy subjects. Distribution The degree of binding of venlafaxine to human plasma proteins is 27% ±2% at concentrations ranging from 2.5 to 2215 ng/mL, and the degree of ODV binding to human plasma proteins is 30%±12% at concentrations ranging from 100 to 500 ng/mL. Protein-binding-induced drug interactions with concomitantly administered venlafaxine are not expected. Following intravenous administration, the steady-state volume of distribution of venlafaxine is 4.4±1.9 L/kg, indicating that venlafaxine distributes well beyond the total body water. Metabolism Following absorption, venlafaxine undergoes extensive pre-systemic metabolism in the liver. The primary metabolite of venlafaxine is ODV, but venlafaxine is also metabolised to N-desmethylvenlafaxine, N,O-didesmethylvenlafaxine, and other minor metabolites. In vitro studies indicate that the formation of ODV is catalysed by CYP2D6 and that the formation of N-desmethylvenlafaxine is catalysed by CYP3A3/4. The results of the in vitro studies have been confirmed in a clinical study with subjects who are CYP2D6-poor and -extensive metabolisers. However, despite the metabolic differences between the CYP2D6-poor and -extensive metabolisers, the total exposure to the sum of the two active species (venlafaxine and ODV) was similar in the two metaboliser groups. Therefore, CYP2D6-poor and -extensive metabolisers can be treated with the same regimen of EFEXOR-XR (see Interactions with Other Drugs, CYP2D6 Inhibitors). Excretion Approximately 87% of a venlafaxine dose is recovered in the urine within 48 hours after a single radio-labelled dose as either unchanged venlafaxine (5%), unconjugated ODV (29%), conjugated ODV (26%), or other minor inactive metabolites (27%), and 92% of the radioactive dose is recovered within 72 hours. Therefore, renal elimination of venlafaxine and its metabolites is the primary route of excretion. Food-Drug Interactions Administration of EFEXOR-XR with food has no effect on the absorption of venlafaxine or on the subsequent formation of ODV. Subject age and sex do not significantly affect the pharmacokinetics of venlafaxine. A 20% reduction in clearance was noted for ODV in subjects over 60 years old; this was probably caused by the decrease in renal function that typically occurs with aging. In some patients with compensated hepatic cirrhosis, the pharmacokinetic disposition of both venlafaxine and ODV was significantly altered. The reduction in both the metabolism of venlafaxine and elimination of ODV resulted in higher plasma concentrations of both venlafaxine and ODV. In patients with moderate to severe impairment of renal function, the total clearance of both venlafaxine and ODV was reduced, and t½ was prolonged. The reduction in total clearance was most pronounced in subjects with creatinine clearance less than 30 mL/min. Clinical Trials Use in Major Depression Three double blind, placebo controlled trials, of up to 12 weeks duration, have examined the clinical efficacy of EFEXOR-XR in the treatment of major depression. One of these studies also incorporated an active comparator, paroxetine. These studies showed EFEXOR-XR to have greater efficacy than both placebo and paroxetine in reducing depression. Use in Generalised Anxiety Disorder Five placebo-controlled trials were conducted to evaluate the efficacy of EFEXOR-XR in the treatment of anxiety. Two trials were eight-week studies, utilizing Efexor-XR doses of 75 mg, 150 mg and 225 mg/day and of 75 mg and 150 mg/day. In one of these, buspirone was found not to be significantly different to placebo or to Efexor- XR. However, Efexor-XR was found to be superior to placebo. Two other trials were the first eight-weeks of two long term studies, utilizing Efexor-XR doses of 75 mg-225 mg/day and of 37.5 mg, 75 mg and 150 mg/day. Four studies demonstrated superiority of Efexor-XR over placebo on at least five of the following efficacy scales: HAM-A total score, the HAM-A psychic anxiety factor, the Hospital Anxiety and Depression (HAD) anxiety subscale, and the CGI severity of illness scale, as well as the HAM-A anxious mood and tension item. Two of these four studies continued for up to six months. These two studies, which utilized Efexor-XR doses of 75 mg-225 mg/day and 37.5 mg, 75 mg and 150 mg/day demonstrated superiority of Efexor-XR over placebo on the HAM-A total score, HAM-A psychic anxiety factor, the HAD anxiety factor, and the CGI severity of illness scale, as well as the HAM-A anxious mood item. The fifth trial was a short-term (8-week) comparison of the efficacy of 2 fixed doses of EFEXOR-XR (75 mg and 150 mg) with placebo and diazepam followed by a comparison of the long-term (6-month) efficacy of EFEXOR-XR and placebo in the prevention of relapse. The most important results were the primary efficacy variables at week 8 using an LOCF analysis. These demonstrated no significant differences between either venlafaxine and placebo, or diazepam and placebo for any of the primary efficacy variables. In view of this failure to demonstrate any effectiveness of either venlafaxine or diazepam over placebo, the long-term outcomes of this study are not of clinical or theoretical value. In conclusion, this study showed no anxiolytic effect of either diazepam or placebo in the short-term (8 week phase). Baseline and Final Mean HAM-A Total and CGI Severity Scores for Placebo-Controlled GAD Studies Study Number ----------- HAM-A Total----------- ----------- CGI Severity --------- Treatment n Baseline Final n Baseline Final 210 (8-week study) Placebo 96 24.1 14.7 96 4.4 3.2 Venlafaxine XR (mg) 75 86 24.7 13.5 86 4.5 3.0 150 81 24.5 12.3 81 4.5 2.9 225 86 23.6 11.9 86 4.4 2.8 214 (8-week study) Placebo 98 23.7 15.4 98 4.3 3.3 Venlafaxine XR (mg) 75 87 23.7 13.0 87 4.2 2.8 150 87 23.0 13.6 87 4.2 3.0 Buspirone 93 23.8 14.3 93 4.2 3.2 218 (6-month study) Placebo 123 24.9 16.2 123 4.4 3.5 Venlafaxine XR (mg) 75-225 115 25.0 11.6 115 4.4 2.7 377 (8-week period) Placebo 96 27.7 15.1 89 4.8 3.2 Venlafaxine XR (mg) 75 181 28.0 12.8 160 4.9 2.9 150 169 28.0 14.2 146 4.9 3.1 epam 89 28.4 13.5 79 4.8 2.9 378 (6-month study) Placebo 129 26.7 15.6 129 4.6 3.2 Venlafaxine XR (mg) 37.5 138 26.6 12.6 138 4.4 2.6 75 130 26.3 10.4 129 4.4 2.4 150 131 26.3 9.5 131 4.6 2.2 Depression Relapse/Recurrence A long-term study of depressed outpatients who had responded to EFEXOR-XR during an initial 8-week open-label treatment phase and were randomly assigned to continuation on EFEXOR-XR or placebo for 6 months demonstrated a significantly lower relapse rate for patients taking EFEXOR-XR compared with those on placebo. In a second long-term study, outpatients with a history of recurrent depression who had responded to EFEXOR (the immediate-release form of venlafaxine) by 8 weeks and maintained improvement during an initial 6-month open-label treatment phase were randomly assigned to maintenance therapy on EFEXOR or placebo for 12 months. Significantly fewer patients taking EFEXOR compared with those on placebo had a reappearance of depression. Social Anxiety Disorder The efficacy of Efexor-XR as a treatment for social anxiety disorder (also known as social phobia) was established in four double-blind, parallel-group, 12-week, multi-centre, placebo-controlled, flexible- dose studies and one double-blind, parallel-group, 6-month, fixed/flexible-dose study in adult outpatients meeting DSM-IV criteria for Social Anxiety Disorder. Patients received doses in a range of 75-225 mg/day. Efficacy was assessed with the Liebowitz Social Anxiety Scale (LSAS). The LSAS measures the relationship of impairment because of social anxiety disorder symptoms by evaluating a patient's fear and avoidance in a broad range of situations (i.e., 13 performance and 11 social interaction situations). Psychometric studies have shown the LSAS to be a valid and reliable measure of social anxiety.1 The LSAS scale has also been shown to be sensitive to differences between active and placebo treatments.2 The results of these trials are presented in the table below. In these five trials, Efexor-XR was significantly more effective than placebo on change from baseline to endpoint on the LSAS total score. Summary of Results for Primary Efficacy Variable in ITT Patients at Final On-Therapy Visit: 12 week and 6 month Variable Study Number No. of Patients Raw baseline Score Adjusted Final On-therapy Score Adjusted Mean Change from Baseline p-value vs Placebo Treatment Group Short-term (12 week) Studies LSAS Study 1 Placebo 138 86.7 69.0 -19.9 Venlafaxine XRa 133 91.1 57.8 -31.0 <0.001 Study 2b Placebo 135 87.4 66.9 -22.1 Venlafaxine XRa 126 90.8 56.3 -32.8 0.003 Study 3 Placebo 132 83.6 64.5 -19.1 Venlafaxine XRa 129 83.2 47.6 -36.0 <0.001 Paroxetinec 128 83.9 48.1 -35.4 <0.001 Study 4 Placebo 144 86.1 64.3 -22.2 Venlafaxine XR 133 86.2 51.5 -35.0 <0.001 Paroxetine 136 87.2 47.3 -39.2 <0.001 Long-term (6 month) Study LSAS Study 5 Placebo 126 89.3 65.6 -23.5 Venlafaxine XR (total)d 238 89.0 51.2 -37.8 <0.001 Venlafaxine XR 75mg 119 91.8 51.0 -38.1 <0.001 Venlafaxine 150-225mg 119 86.2 51.5 -37.6 <0.001 a: Flexible dose range for venlafaxine XR was 75-225mg/day; b: Data shown are for ITT population; c: Flexible dose range for paroxetine was 20-50mg/day; d: Primary treatment group. Abbreviations: ITT = intent to treat; LSAS = Liebowitz Social Anxiety Scale INDICATIONS EFEXOR-XR is indicated for the treatment of: Major depression Generalised anxiety disorder; Social Anxiety Disorder. EFEXOR-XR is also indicated for the prevention of relapse and recurrence of major depression where appropriate. CONTRAINDICATIONS Hypersensitivity to venlafaxine or any excipients in the formulation Concomitant use of venlafaxine and any monoamine oxidase inhibitor- (MAOI) is contraindicated. EFEXOR-XR must not be initiated for at least 14 days after discontinuation of treatment with a MAOI. EFEXOR- XR must be discontinued for at least 7 days before starting treatment with any MAOI -(See PRECAUTIONS - Interactions with other drugs). PRECAUTIONS Use in Patients with Renal Impairment The total daily dose of venlafaxine must be reduced by 25% to 50% for patients with renal impairment with a glomerular filtration rate (GFR) of 10 to 70 mL/min. The total daily dose of venlafaxine must be reduced by 50% in haemodialysis patients. Administration must be withheld until the dialysis session is completed. Use in Patients with Hepatic Impairment The total daily dose of venlafaxine must be reduced by 50% in patients with moderate hepatic impairment. Reductions of more than 50% may be appropriate for some patients. Sustained Hypertension Dose-related increases in blood pressure have been reported in some patients treated with venlafaxine. Among patients treated with 75 to 375 mg per day of EFEXOR-XR in pre- marketing depression studies, 3% (19/705) experienced sustained hypertension [defined as treatment-emergent supine diastolic blood pressure (SDBP) ( 90 mm Hg and ( 10 mm Hg above baseline for 3 consecutive on-therapy visits]. Among patients treated with 37.5 to 225 mg per day of EFEXOR-XR in pre-marketing GAD studies, 0.5% (5/1011) experienced sustained hypertension. Experience with the immediate-release venlafaxine showed that sustained hypertension was dose-related, increasing from 3 to 7% at 100 to 300 mg per day to 13% at doses above 300 mg per day. An insufficient number of patients received mean doses of EFEXOR-XR over 300 mg per day to fully evaluate the incidence of sustained increases in blood pressure at these higher doses. In placebo-controlled pre-marketing depression studies with EFEXOR- XR 75 to 225 mg per day, a final on-drug mean increase in supine diastolic blood pressure (SDBP) of 1.2 mm Hg was observed for EFEXOR- XR treated patients compared with a mean decrease of 0.2 mm Hg for placebo-treated patients. In placebo-controlled pre-marketing GAD studies with EFEXOR-XR 37.5 to 225 mg per day up to 8 weeks or up to 6 months, a final on-drug mean increase in SDBP of 0.3 mm Hg was observed for EFEXOR-XR treated patients compared with a mean decrease of 0.9 and 0.8 mm Hg, respectively, for placebo-treated patients. In pre-marketing Social Anxiety Disorder studies up to 12 weeks, the final on-therapy mean change from baseline in SDBP was small - an increase of 0.78 mmHg, compared to a decrease of 1.41 mmHg in placebo-treated patients. In a 6-month study, the final on- therapy mean increase from baseline in SDBP with EFEXOR-XR 150 to 225 mg was 1.49 mmHg. The increase was significantly different from the 0.6 mmHg decrease with placebo and the 0.2 mmHg decrease with EFEXOR-XR 75 mg In pre-marketing depression studies, 0.7% (5/705) of the EFEXOR-XR treated patients discontinued treatment because of elevated blood pressure. Among these patients, most of the blood pressure increases were in a modest range (12 to 16 mm Hg, SDBP). In pre-marketing GAD studies up to 8 weeks and up to 6 months, 0.7% (10/1381) and 1.3% (7/535) of the EFEXOR-XR treated patients, respectively, discontinued treatment because of elevated blood pressure. Among these patients, most of the blood pressure increases were in a modest range (12 to 25 mm Hg, SDBP up to 8 weeks; 8 to 28 mm Hg up to 6 months). Sustained increases of SDBP could have adverse consequences. Therefore it is recommended that patients receiving EFEXOR-XR have regular monitoring of blood pressure. For patients who experience a sustained increase in blood pressure while receiving venlafaxine, either dose reduction or discontinuation should be considered. Increase in Serum Cholesterol Clinically relevant increases in serum cholesterol were recorded in 5.3% of EFEXOR immediate release tablet-treated patients and 0.0% of placebo-treated patients for at least 3 months in placebo-controlled clinical trials. Treatment with EFEXOR-XR for up to 12 weeks in pre-marketing placebo- controlled depression trials was associated with a mean final on- therapy increase in serum cholesterol concentration of approximately 0.039 mmol/L (1.5 mg/dL). EFEXOR-XR treatment for up to 8 weeks and up to 6 months in pre-marketing placebo-controlled GAD trials was associated with mean final on-therapy increases in serum cholesterol concentration of approximately 0.026 mmol/L (1.0 mg/dL) and 0.059 mmol/L (2.3 mg/dL), respectively. In the 12 week Social Anxiety Disorder studies, small mean increases in fasting levels of total cholesterol (0.20 mmol/L, 4%) were seen in the EFEXOR-XR-treated group at the final on-therapy evaluation; the increases were significantly different from the changes in the placebo group. In a 6-month study, the final on-therapy mean increase in total cholesterol was higher (0.32mmol/L, 7%) in the EFEXOR-XR 150 to 225 mg group; however the total cholesterol value was slightly decreased (0.01mmol/L) for the EFEXOR-XR group. There were also significant mean increases from baseline in LDL, but not HDL for the EFEXOR-XR 150 to 225 mg group. The final on-therapy increase of 0.213 mmol/L from baseline in LDL with EFEXOR-XR 150 to 225 mg was significantly different from the small decrease with placebo (0.079 mmol/L) and the negligible increase with EFEXOR-XR 75mg (0.006 mmol/L). Measurement of serum cholesterol levels should be considered during long-term treatment. Hyponatraemia Cases of hyponatraemia, and/or the Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH) may occur with venlafaxine, usually in volume-depleted or dehydrated patients, including elderly patients and in patients taking diuretics. These have resolved on discontinuation of the drug. Caution is advised in administering EFEXOR-XR to patients with diseases or conditions that could affect haemodynamic responses or metabolism. Myocardial Infarction and Unstable Heart Disease Venlafaxine has not been evaluated in patients with a recent history of myocardial infarction or unstable heart disease. Therefore it should be used with caution in these patients. Patients with these diagnoses were systematically excluded from any clinical studies during the product's trials. Evaluation of the electrocardiograms for 769 patients who received immediate release EFEXOR in 4 to 6-week double blind, placebo- controlled trials showed that the incidence of trial-emergent conduction abnormalities did not differ from that with placebo. The electrocardiograms for patients who received EFEXOR-XR or placebo in the depression GAD and Social Anxiety Disorder trials were analysed. The mean change from baseline in corrected QT interval (QTc) for EFEXOR-XR treated patients in depression studies was increased relative to that for placebo-treated patients (increase of 4.7 msec for EFEXOR-XR and decrease of 1.9 msec for placebo). The mean change from baseline QTc for EFEXOR-XR treated patients in the GAD studies did not differ significantly from placebo. The final on-therapy mean increase from baseline in QTc (3 msec) was significant for Efexor-XR treated patients in the Social Anxiety Disorder short-term studies. In the 6 month study, the final on-therapy mean increase from baseline in QTc with EFEXOR-XR 150 to 225 mg (3 msec) was significant, but the increase was not significantly different from the small mean increase (0.5 msec) with placebo. The value for EFEXOR-XR 75mg was a 0.05 msec decrease. Increases in heart rate may occur, particularly with higher doses. Therefore caution is advised in patients whose underlying conditions may be compromised by increases in heart rate. The mean change from baseline in heart rate for EFEXOR-XR treated patients in both the GAD and depression studies was significantly higher than for placebo (a mean increase of 3-4 beats per minute for EFEXOR-XR and 0-1 beat per minute for placebo in the GAD and depression studies respectively). In the pooled short-term Social Anxiety Disorder studies, the final on-therapy mean increase from baseline in heart rate with EFEXOR-XR was 5 beats per minute. In the 6 month study, the final on-therapy mean increases from baseline in heart rate were significant with EFEXOR-XR 75 (2 beats per minute) and EFEXOR-XR 150 to 225 mg (6 beats per minute); however only the increase with the higher dose was significantly different from the small increase with placebo (0.4 beats per minute). The clinical significance of these changes is unknown. Mydriasis Mydriasis may occur in association with venlafaxine. It is recommended that patients with raised intra-ocular pressure or patients at risk for acute narrow-angle glaucoma should be closely monitored. Abrupt Discontinuation of Efexor-XR Discontinuation effects are well known to occur with antidepressants. Discontinuation symptoms have been assessed both in patients with depression and in those with anxiety. Abrupt discontinuation, dose reduction, or tapering of venlafaxine at various doses has been found to be associated with the appearance of new symptoms, the frequency of which increased with increased dose level and with longer duration of treatment. Symptoms reported included agitation, anorexia, anxiety, confusion, dry mouth, fatigue, paraesthesias, vertigo, hypomania, nausea, vomiting, dizziness, convulsion, headache, diarrhoea, sleep disturbance, insomnia, somnolence, sweating and nervousness. Where such symptoms occurred, they were usually self-limiting, but in a few patients lasted for several weeks. There is also a report of a withdrawal syndrome, confirmed by two challenges in a 32-year-old woman who had received venlafaxine 300 mg daily for 8 months. It is, therefore, recommended that the dosage of EFEXOR-XR be tapered gradually and the patient monitored. The period required for discontinuation may depend on the dose, duration of therapy and the individual patient (See DOSAGE AND ADMINISTRATION). Altered Weight Weight changes, either losses or gains, do not appear to present a clinically important feature of venlafaxine treatment. Clinically significant weight gain or loss was seen in less than 1% of patients treated with venlafaxine during clinical trials. A dose-dependent weight loss (mean loss <1 kg) was noted in some patients treated with venlafaxine during the first few months of venlafaxine treatment. After month 9, the mean weight began to increase slightly but significantly, an effect often seen with tricyclic antidepressant therapy. Significant weight loss (> 7 kg) was seen in 6 (0.3%) of 2,181 patients, compared to no patients treated with placebo and 0.2% of patients treated with a comparative antidepressant. The safety and efficacy of venlafaxine therapy in combination with weight loss agents, including phentermine, have not been established. Co-administration of EFEXOR-XR and weight loss agents is not recommended. EFEXOR-XR is not indicated for weight loss alone or in combination with other products. Suicide The risk of suicide attempt must be considered in all depressed patients. Prescriptions for EFEXOR-XR should be written for the smallest quantity of capsules consistent with good patient management in order to reduce the possibility of overdosage. Seizures Seizures may occur with venlafaxine therapy. EFEXOR-XR, as with all antidepressants, should be introduced with care, in patients with a history of seizure disorders. EFEXOR-XR should be discontinued in any patient who develops seizures. Activation of Mania/Hypomania Mania/hypomania may occur in a small proportion of patients with mood disorders treated with antidepressants, including venlafaxine. Venlafaxine should be used cautiously in patients with a history of mania. Skin/Allergic Reactions Patients should be advised to notify their physician if they develop a rash, hives, or related allergic phenomena Skin and Mucous Membrane Bleeding The risk of skin and mucous membrane bleeding may be increased in patients taking venlafaxine, particularly if predisposed to such events. Venlafaxine should be used cautiously in patients predisposed to bleeding at these sites. Effects on Cognitive and Motor Performance Although venlafaxine has been shown not to affect psychomotor, cognitive or complex behaviour performance in healthy volunteers, any psychoactive medication may impair judgment, thinking or motor skills, and patients should be cautioned about operating hazardous machinery, including automobiles, until they are reasonably certain that the treatment does not affect them adversely. Physical and Psychological Dependence Clinical studies have shown no evidence of drug-seeking behaviour, development of tolerance, or dose escalation over time among patients taking venlafaxine. Consequently, physicians should carefully evaluate patients for a history of drug abuse and follow such patients closely observing them for signs of misuse or abuse of venlafaxine (e.g. development of tolerance, increase in dose, drug- seeking behaviour) (see PHARMACOLOGY). Use in Elderly Patients No overall differences in effectiveness or safety were observed between elderly (aged 65 years and older) and younger patients. EFEXOR-XR does not appear to pose any exceptional safety problems for healthy elderly patients. Effectiveness in elderly patients with social anxiety disorder has not been established. Paediatric Use Safety and effectiveness in individuals below 18 years of age have not been established. Efexor-XR should not be used in such patients. As with adults, decreased appetite, weight loss, increased blood pressure and increased serum cholesterol have been observed in children and adolescents aged 6 to 17 years. In paediatric clinical trials, there were increased reports of hostility and, especially in major depressive disorder, suicide- related adverse events such as suicidal ideation and self-harm. Carcinogenesis, Mutagenesis, Impairment of Fertility Evidence of impairment of fertility was not noted in preclinical toxicology studies. Venlafaxine was given by oral gavage to mice and rats for 18 months and 24 months respectively, at dosages up to 120 mg/kg/day. There were no clear drug-related oncogenic effects in either species. In these studies, animal exposure to the main human metabolite ODV was less, and exposure to venlafaxine was more than would be expected in humans taking the recommended therapeutic and maximum doses. There was no evidence of gene mutation or chromosomal change in a series of genotoxicity assays using venlafaxine and the main human metabolite ODV. Signs of pharmacologic toxicity were seen in paternal and maternal rats given venlafaxine doses of 30 and 60 mg/kg/day, but no adverse effect was noted in fertility or general reproductive performance. Decreased foetal size and pup weight at birth with 60 mg/kg/day may be correlated with maternal toxicity. Use During Pregnancy Category: B2 The safety of venlafaxine in human pregnancy has not been established. There are no adequate and well-controlled studies in pregnant women. Because animal reproductive studies are not always predictive of human response, this medication should be used during pregnancy only if clearly needed. Patients should be advised to notify their physician if they become pregnant or intend to become pregnant during therapy. If venlafaxine is used until or shortly before birth, discontinuation effects in the newborn should be considered. In a rat teratology study, venlafaxine was given orally at dosages up to 80 mg/kg/day (approximately 11 times the maximum recommended human dose). Foetotoxicity evidenced by growth retardation was slightly increased at 80 mg/kg/day, an effect which may be related to maternal toxicity at this dose level. Foetal survival and morphologic development were not affected. In another teratology study, rabbits were given venlafaxine dosages up to 90 mg/kg/day. Foetotoxicity evidenced by resorption and foetal loss was slightly increased at 90 mg/kg/day; (approximately 12 times the maximum recommended human dose). These effects could be correlated with maternal toxicity. No venlafaxine-associated teratogenic effect was noted in either species at any dosage, though there was an increased incidence of 'W'-shaped apex of the heart in the rabbit study. In these studies, animal exposure to the main human metabolite ODV was less, and estimated exposure to venlafaxine was approximately 6-fold more than would be expected in humans taking the recommended therapeutic and maximum doses. In rats, estimated exposure to venlafaxine was more than the expected human exposure. No teratogenic effect was seen. In a perinatal toxicity study in rats after oral dosing of dams with 30 mg/kg or more, decreased pup survival following birth was observed. This effect is secondary to treatment-decreased maternal care, and is also seen with other antidepressants. Use During Lactation Venlafaxine and/or its metabolites are secreted in milk of lactating rats at concentrations higher than those found in the plasma of the dam. Venlafaxine and its metabolites have been shown to pass into human milk. The total dose of venlafaxine and O-desmethylvenlafaxine ingested by breast fed infants can be as high as 9.2% of maternal intake. Therefore, the use of EFEXOR-XR in nursing women cannot be recommended. Exposed infants should be observed closely. Interactions with other Drugs Venlafaxine and ODV are 27% and 30% bound to plasma proteins respectively, therefore interactions due to protein binding of venlafaxine and the major metabolite are not expected. Monoamine oxidase inhibitors Concomitant use with EFEXOR is contraindicated. Irreversible MAOI Inhibitors Severe adverse reactions have been reported in patients who have recently been discontinued from a MAOI and started on venlafaxine, or have recently had venlafaxine therapy discontinued prior to initiation of a MAOI or when these two agents are co-administered. Reactions have included tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome and/or serotonergic syndrome, seizures, and death. Do not use EFEXOR in combination with a MAOI or within at least 14 days of discontinuing MAOI treatment. Allow at least 7 days after stopping EFEXOR-XR before starting a MAOI (see CONTRAINDICATIONS). Reversible MAOI Inhibitors EFEXOR should not be administered concomitantly with moclobemide. There are no clinical trials to support the recommendation of a specific time between discontinuing treatment with the reversible MAOI, moclobemide and initiating EFEXOR therapy or switching to moclobemide. Given the risk for adverse reactions described for irreversible MAOIs (see above), an adequate washout period should be ensured when switching a patient between EFEXOR and moclobemide. The appropriate washout period should take into account the pharmacological properties of venlafaxine and moclobemide and the clinician's assessment of the individual patient. Based on the half- lives of moclobemide, venlafaxine and ODV, the minimum washout period should be 24 hours when switching from moclobemide to EFEXOR and 7 days when switching from EFEXOR to moclobemide. Warfarin There have been reports of increases in prothrombin time, partial thromboplastin time, or INR when venlafaxine was given to patients receiving warfarin therapy. Alcohol Venlafaxine has not been shown to increase the impairment of mental and motor skills caused by ethanol. However, as with all CNS active drugs, patients should be advised to avoid alcohol consumption while taking EFEXOR. Cimetidine Cimetidine inhibited the first-pass metabolism of venlafaxine but had no apparent effect on the formation or elimination of ODV, which is present in much greater quantity in the systemic circulation. No dosage adjustment seems necessary when EFEXOR is co-administered with cimetidine. However, for elderly patients or patients with hepatic dysfunction, the interaction could potentially be more pronounced and for such patients clinical monitoring is indicated when EFEXOR is administered with cimetidine. epam. The pharmacokinetic profiles of venlafaxine and ODV were not altered when venlafaxine and diazepam were administered together to healthy volunteers. Venlafaxine had no effect on the pharmacokinetics of diazepam or affect the psychomotor and psychometric effects induced by diazepam. Lithium The steady-state pharmacokinetics of venlafaxine and ODV are not affected when lithium is co-administered. Venlafaxine also has no effect on the pharmacokinetics of lithium. (See also CNS Active drugs.) Haloperidol Venlafaxine administered under steady-state conditions (75 mg twice daily) to 24 healthy subjects decreased total oral clearance (Cl/F) of a single 2 mg dose of haloperidol by 42%, which resulted in a 70% increase in haloperidol AUC. In addition, the haloperidol Cmax increased 88% when co-administered with venlafaxine, but the haloperidol elimination half-life (t½) was unchanged. The mechanism explaining this finding is unknown. Imipramine Venlafaxine did not affect the CYP2D6-mediated 2-hydroxylation of imipramine or its active metabolite, desimipramine, which indicates that venlafaxine does not inhibit the CYP2D6 isoenzyme. However, the renal clearance of 2-hydroxydesimipramine was reduced with co- administration of venlafaxine. Imipramine partially inhibited the CYP2D6-mediated formation of ODV, however, the total concentrations of active compounds (venlafaxine plus ODV) was not affected with imipramine administration. Additionally, in a clinical study involving CYP2D6-poor and - extensive metabolisers, the total sum of the two active species (venlafaxine and ODV) was similar in the two metaboliser groups. Therefore, no dosage adjustment is expected when venlafaxine is co- administered with a CYP2D6 inhibitor. However, desipramine AUC, Cmax, and Cmin increased by about 35% in the presence of venlafaxine. There was an increase of 2-OH-desipramine AUC by 2.5 to 4.5 fold. The clinical significance of this finding is unknown. Risperidone Venlafaxine increased risperidone AUC by 32% but did not significantly alter the pharmacokinetic profile of the total active moiety (risperidone plus 9-hydroxy-risperidone). The clinical significance of this interaction is unknown. Indinavir A pharmacokinetic study with indinavir has shown a 28% decrease in AUC and a 36% decrease in Cmax for indinavir. Indinavir did not affect the pharmacokinetics of venlafaxine and ODV. The clinical significance of this interaction is unknown. Antihypertensive and Hypoglycaemic Agents Retrospective analysis of study events occurring in patients taking venlafaxine concurrently with antihypertensive or hypoglycaemic agents in clinical trials provided no evidence suggesting incompatibility between treatment with venlafaxine and treatment with either antihypertensive or hypoglycaemic agents. CNS Active Drugs Based on the known mechanism of action of venlafaxine and the potential for serotonin syndrome, caution is advised when EFEXOR is co-administered with other drugs that may affect the serotonergic neurotransmitter systems (such as triptans, SSRIs or lithium). No information is available on the use of EFEXOR in combination with opiates. There have been reports of elevated clozapine levels in association with adverse events including seizures, following the administration of venlafaxine. As with other antidepressants, co-administration of EFEXOR and products containing Hypericum perforatum (St. 's Wort) is not recommended due to possible pharmacodynamic interactions. Drugs that Inhibit Cytochrome P450 Isoenzymes CYP2D6 Inhibitors In vitro and in vivo studies indicate that venlafaxine is metabolised predominantly to ODV by CYP2D6, the isoenzyme that is responsible for the genetic polymorphism seen in the metabolism of many antidepressants. Therefore the potential exists for a drug interaction between drugs that inhibit CYP2D6-mediated metabolism (such as amiodarone and quinidine) and venlafaxine. Drug interactions that reduce the metabolism of venlafaxine to ODV potentially increase the plasma concentrations of venlafaxine and lower the concentration of the active metabolite. The concomitant use of venlafaxine with drug treatment(s) that potentially inhibits both CYP2D6 and CYP3A4, the primary metabolising enzymes for venlafaxine, has not been studied. Therefore caution is advised if a patient's therapy includes venlafaxine and any agent(s) that produces simultaneous inhibition of these two enzyme systems. CYP3A4 Inhibitors In vitro studies indicate that venlafaxine is likely metabolised to a minor, less active metabolite, N-desmethylvenlafaxine, by CYP3A4. Because CYP3A4 is a minor pathway relative to CYP2D6 in the metabolism of venlafaxine, the potential for a clinically significant drug interaction between inhibitors of CYP3A4-mediated metabolism (such as erythromycin, fluconazole and grapefruit juice) and venlafaxine is small. Drugs Metabolised by Cytochrome P450 Isoenzymes In vitro studies indicate that venlafaxine is a relatively weak inhibitor of CYP2D6 and that venlafaxine does not inhibit CYP1A2, CYP2C9 or CYP3A4. Some of these findings have been confirmed with drug interaction studies between venlafaxine and imipramine (metabolised by CYP2D6) and diazepam (metabolised by CYP2C19). Therefore, EFEXOR-XR is not expected to interact with other drugs metabolised by these isoenzymes. Electroconvulsive Therapy There are no clinical data establishing the benefit of EFEXOR-XR combined with electroconvulsive therapy. Effects on Laboratory tests No interference on laboratory tests by venlafaxine is known. ADVERSE REACTIONS Adverse reactions are listed in the following table in CIOMS frequency categories: Common: = 1%; Uncommon: = 0.1% and <1%; Rare: = 0.01% and <0.1%; Very rare: <0.01%. Body System Adverse Reactions Body As A Whole Common: Asthenia/fatigue. Uncommon: Photosensitivity reaction. Very rare: Anaphylaxis. Cardiovascular Common: Hypertension, vasodilatation (mostly hot flashes/flushes). Uncommon: Hypotension, postural hypotension, syncope, tachycardia. Very rare: QT prolongation, ventricular fibrillation, ventricular tachycardia (including torsade de pointes). Digestive Common: Appetite decreased, constipation, nausea, vomiting. Uncommon: Bruxism. Undetermined Frequency: Pancreatitis. Haematological/Lymphatic Uncommon: Ecchymosis, mucous membrane bleeding. Rare: Prolonged bleeding time, thrombocytopenia. Undetermined Frequency: Blood dyscrasias (including agranulocytosis, aplastic anemia, neutropenia and pancytopenia) Metabolic/Nutritional Common: Serum cholesterol increased (particularly with prolonged administration and with higher doses), weight loss. Uncommon: Abnormal liver function tests, hyponatraemia, weight gain. Rare: Hepatitis, syndrome of inappropriate antidiuretic hormone secretion (SIADH). Undetermined Frequency: Prolactin increased. Musculoskeletal Undetermined Frequency: Rhabdomyolysis. Nervous Common: Abnormal dreams, decreased libido, dizziness, dry mouth, increased muscle tonus, insomnia, nervousness, paraesthesia, sedation, tremor. Uncommon: Apathy, hallucinations, myoclonus. Rare: Convulsion, manic reaction, neuroleptic malignant syndrome (NMS), serotonergic syndrome. Undetermined Frequency: Agitation, delirium, extrapyramidal reactions (including dystonia, and dyskinesia), tardive dyskinesia. Respiratory Common: Yawning. Undetermined Frequency: Pulmonary eosinophilia. Skin Common: Sweating (including Night Sweats). Uncommon: Rash, alopecia. Very Rare: Erythema multiforme, s- syndrome. Special Senses Common: Abnormality of accommodation, mydriasis, visual disturbance. Uncommon: Altered taste sensation. Undetermined Frequency: Tinnitus. Urogenital Common: Abnormal ejaculation/orgasm (males), anorgasmia, erectile dysfunction, urination impaired (mostly hesitancy) Uncommon: Abnormal orgasm (females), menorrhagia, urinary retention, proteinuria. Discontinuation effects are well known to occur with antidepressants, and it is therefore recommended that the dosage is tapered gradually and the patient monitored (see DOSAGE AND ADMINISTRATION). The following symptoms have been reported in association with abrupt discontinuation or dose-reduction, or tapering of treatment: hypomania, anxiety, agitation, nervousness, confusion, insomnia or other sleep disturbances, fatigue, somnolence, paraesthesia, dizziness, convulsion, vertigo, headache, sweating, dry mouth, anorexia, diarrhoea, nausea, and vomiting. The majority of discontinuation reactions are mild and resolve without treatment. In the Social Anxiety Disorder pooled short-term studies, the most common taper/post-study-emergent adverse events were dizziness (13%), nausea (7%), insomnia (3%), nervousness (3%) and asthenia (2%). In the 6-month study, the most common taper/post-study treatment emergent adverse events were dizziness (21% and 16%) and nausea (7% and 10%) for EFEXOR-XR 75 mg and EFEXOR-XR 150-225 mg, respectively. Paediatric Patients (see PRECAUTIONS - Paediatric Use) In general, the adverse reaction profile of venlafaxine in placebo- controlled clinical trials in children and adolescents (aged 6 to 17) was similar to that seen for adults. As with adults, decreased appetite, weight loss, increased blood pressure and increased serum cholesterol were observed. Additionally, the following adverse reactions were observed: abdominal pain, agitation, dyspepsia, ecchymosis, epistaxis and myalgia. In paediatric clinical trials, there were increased reports of hostility and, especially in major depression, suicide-related adverse events such as suicidal ideation and self-harm. DOSAGE AND ADMINISTRATION Usual Dose The usual recommended dose for the treatment of major depression, generalised anxiety disorder or social anxiety disorder is 75 mg per day given once daily. After two weeks, the dose may be increased to 150 mg per day given once daily if further clinical improvement is required. If needed, this can be increased up to 375 mg given once daily. Dose increments should be made at intervals of approximately 2 weeks or more, but not less than 4 days. Antidepressant activity with the 75 mg dose was observed after 2 weeks of treatment and anxiolytic activity was observed after one week. It is recommended that EFEXOR-XR be taken with food. Each capsule should be swallowed whole with fluid. Do not divide, crush, chew or place the capsule in water. EFEXOR-XR should be administered once daily, at approximately the same time either in the morning or in the evening. Depressed patients who are currently being treated at a therapeutic dose with immediate-release venlafaxine may be switched to EFEXOR-XR or vice versa at the nearest equivalent dose (mg/day). However, individual dosage adjustments may be necessary. Patients with Renal or Hepatic Impairment Patients with renal and/or hepatic impairment should receive lower doses of EFEXOR-XR. It may be necessary to initiate treatment in these patients with immediate-release venlafaxine tablets. Patients whose glomerular filtration rate (GFR) is less than 30 mL/min should have their dosage reduced by 50%. Haemodialysis clearances of both venlafaxine and ODV in humans are low. Nonetheless, it is recommended that the daily dose of EFEXOR-XR be withheld from patients who require dialysis treatment until after completion of the dialysis treatment. Patients with moderate hepatic impairment should also have their dosage reduced by 50%. Further reductions in dosage should be considered for patients with more severe degrees of hepatic impairment. Elderly Patients No adjustment in the usual dose is recommended for elderly patients solely because of their age. As with any antidepressant, however, caution should be exercised in treating the elderly. When individualising the dosage, extra care should be taken when increasing the dose. Maintenance/Continuation/Extended Treatment The physician should periodically re-evaluate the usefulness of long- term EFEXOR-XR treatment for the individual patient. It is generally agreed that acute episodes of major depression require several months or longer of sustained pharmacological therapy. Whether the dose of antidepressant needed to induce remission is identical to the dose needed to maintain and/or sustain euthymia is unknown. Usually, the dosage for prevention of relapse or for prevention of recurrence of a new episode is similar to that used during initial treatment. Patients should be regularly re-assessed in order to evaluate the benefit of long-term therapy. In Social Anxiety Disorder, continuing therapeutic benefit has been established for periods of up to 6 months. The need for continuing medication in patients with Social Anxiety Disorder who improve with EFEXOR-XR treatment should be periodically assessed. Discontinuing EFEXOR-XR When EFEXOR-XR at a dose of 75 mg/day or greater has been administered for more than 1 week is stopped, it is generally recommended that the dose be tapered gradually to minimise the risk of discontinuation symptoms. Patients who have received EFEXOR-XR for 6 weeks or more should have their dose tapered gradually over at least a 2-week period. To facilitate tapering below 75 mg of Efexor- XR, physicians may consider switching some patients from 75 mg of Efexor-XR once daily to 37.5 mg venlafaxine immediate-release tablets twice daily, and then to 37.5 mg venlafaxine immediate- release tablets once daily (see also Usual Dosage above). The period required for tapering may depend on the dose, duration of therapy, and the individual patient. Patients should be advised to consult their physician before abruptly discontinuing EFEXOR-XR. OVERDOSAGE In managing overdosage, consider the possibility of multiple medication involvement. The physician should consider contacting a poison control centre on the treatment of any overdose. (See PRECAUTIONS - Interactions with other drugs). During pre-marketing trials, most patients who have overdosed with venlafaxine were asymptomatic. Of the remainder, somnolence was the most commonly reported symptom. Mild sinus tachycardia and mydriasis have also been reported. There were no reports of seizures, respiratory distress, significant cardiac disturbances, or significant laboratory test result abnormalities among any of the cases reported to date. However, seizures and respiratory distress occurred in one patient in an on-going study who ingested an estimated 2.75g of venlafaxine with naproxen and thyroxine. Generalised convulsions and coma resulted and emergency resuscitation was required. Recovery was good without sequelae. In post-marketing experience, electrocardiogram changes (e.g. prolongation of QT interval, bundle branch block, QRS prolongation), sinus and ventricular tachycardia, bradycardia, hypotension, vertigo, change in level of consciousness (ranging from somnolence to coma), and seizures have been reported in association with overdosage of venlafaxine, either alone or in combination with other drugs and/or alcohol. Such events are rare and usually resolved spontaneously. Also from post-marketing experience, there have been reports of fatalities in patients taking overdoses of venlafaxine, predominantly in combination with alcohol and/or other drugs. Management of Overdosage General supportive and symptomatic measures are recommended. Ensure an adequate airway, oxygenation and ventilation. Cardiac rhythm and vital signs must be monitored. Administration of activated charcoal may also limit drug absorption. Where there is a risk of aspiration, induction of emesis is not recommended. No specific antidotes for venlafaxine are known. Forced diuresis, dialysis, haemoperfusion and exchange transfusion are unlikely to be of benefit. Venlafaxine and ODV are not considered dialyzable because haemodialysis clearance of both compounds is low. PRESENTATION EFEXOR-XR is available for oral use as opaque peach (75 mg) or opaque dark orange (150 mg) modified release capsules with a 'W' and strength printed in red or white, respectively. EFEXOR-XR is packed in blister packs in pack sizes of 7 and 28. MEDICINE CLASSIFICATION PRESCRIPTION ONLY MEDICINE STORAGE Store below 30°C. NAME AND ADDRESS Wyeth (NZ) Limited 15B Vestey Drive, Mt Wellington, AUCKLAND Phone: (09) 573 5100 ®Registered Trade mark Date of preparation: 9 December 2003 > Hi, I'm new. I haven't read much of the board yet, but I thought I > would post the link to the ACNP Task Force " PRELIMINARY REPORT OF THE > TASK FORCE ON SSRIs AND SUICIDAL BEHAVIOR IN YOUTH " > > http://www.acnp.org/exec_summary.pdf > > Please note that members of the task force are also the researchers > who did some of the original studies that were reviewed. Also check > the drug company connections of the task force members listed in the > final pages. > > I would also like to point out the the single most effective and > safest treatment for depression has consistently been proven by the > drug companies clinical double blind studies to be the placebo. In > most (all?) cases, the studied medication out perform the placebo by > less than 20%, often in the 5-10% range while the improvement rate for > the placebo was consistently above 35%, in at least one case as high > as 60%. The more the researchers refine the definition of improvement > in depressive symptoms so that the drug scores higher, the placebo > also scores higher. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 25, 2004 Report Share Posted January 25, 2004 Dear As you said " Hi, I'm new................. " *********** You are welcome to join in our debate " I haven't read much of the board yet,........... " READ THIS PLEASE and COMMENT upon the info provided by the DRUG maker respectfully morse Effexor maker (Wyeth) ADMITS to PAEDIATRIC suicidal ideation in it's OWN DATA files http://www.medsafe.govt.nz/profs/Datasheet/e/Efexorxrcap.htm " Paediatric Use Safety and effectiveness in individuals below 18 years of age have not been established. Efexor-XR should not be used in such patients. As with adults, decreased appetite, weight loss, increased blood pressure and increased serum cholesterol have been observed in children and adolescents aged 6 to 17 years. In paediatric clinical trials, there were increased reports of hostility and, especially in major depression, suicide-related adverse events such as suicidal ideation and self-harm.............. " Data Sheet EFEXOR®-XR (Venlafaxine Hydrochloride) Modified Release Capsules NAme of drug EFEXOR-XR Venlafaxine hydrochloride 75 mg and 150 mg modified release capsules. DESCRIPTION EFEXOR-XR capsules are an extended-release formulation, which release the active constituent, venlafaxine hydrochloride, from spheroids within the capsule. Drug release is controlled by diffusion through the coating membrane on the spheroids and is not pH dependent. Two strengths of EFEXOR-XR capsules are available containing either 75 mg or 150 mg of venlafaxine (as hydrochloride). Venlafaxine hydrochloride is chemically defined (R/S)-1-[(2- dimethylamino)-1-(4-methoxyphenyl)ethyl] cyclohexanol hydrochloride. It is a white to off-white crystalline solid with a solubility of 572 mg/mL in water (adjusted to ionic strength of 0.2 M with sodium chloride). Its molecular weight is 313.87. Other ingredients are cellulose-microcrystalline, ethylcellulose, hypromellose, gelatin, red iron oxide CI 77491, yellow iron oxide CI 77492, titanium dioxide and talc purified. PHARMACOLOGY Actions Venlafaxine is a structurally novel antidepressant for oral administration; it is chemically unrelated to tricyclic, tetracyclic, or other available antidepressant agents. The antidepressant action of venlafaxine in humans is believed to be associated with its potentiation of neurotransmitter activity in the central nervous system. Preclinical studies have shown that venlafaxine and its major metabolite, O-desmethylvenlafaxine (ODV), are potent inhibitors of serotonin and noradrenaline reuptake, and also weakly inhibit dopamine reuptake. Venlafaxine is a racemate. The R-enantiomer is relatively more potent than the S-enantiomer with regard to inhibition of noradrenaline reuptake; the S- enantiomer is more potent regarding inhibition of serotonin reuptake. Both enantiomers are more potent on serotonin compared to noradrenaline reuptake. The enantiomers of ODV also inhibit both noradrenaline and serotonin reuptake, with the R-enantiomer being more potent. Venlafaxine and its major metabolite appear to be equipotent with respect to their overall action on neurotransmitter re-uptake and receptor binding. Studies in animals show that tricyclic antidepressants may reduce ß-adrenergic receptor responsiveness following chronic administration. In contrast, venlafaxine and ODV reduce ß-adrenergic responsiveness after both acute (single dose) and chronic administration. Venlafaxine has no significant affinity for rat brain muscarinic, H1- histaminergic or a1-adrenergic receptors in vitro. Pharmacological activity at these receptors is potentially associated with various sedative, cardiovascular, and anticholinergic effects seen with other psychotropic drugs. Venlafaxine does not possess monoamine oxidase (MAO) inhibitory activity. In vitro studies revealed that venlafaxine has virtually no affinity for opiate, benzodiazepine, phencyclidine (PCP), or N-methyl-D- aspartic acid (NMDA) receptors. Venlafaxine also does not produce noradrenaline release from brain slices. It has no significant central nervous system (CNS) stimulant activity in rodents. In primate drug discrimination studies, venlafaxine showed no significant stimulant or depressant abuse liability. Pharmacokinetics Steady-state concentrations of venlafaxine and ODV are attained within 3 days of oral multiple-dose therapy. Venlafaxine and ODV exhibited linear kinetics over the dose range of 75 to 450 mg/day. Mean±SD steady-state plasma clearance of venlafaxine and ODV is 1.3±0.6 and 0.4±0.2 L/h/kg, respectively; apparent elimination half- life is 5±2 and 11±2 hours, respectively; and apparent (steady- state) volume of distribution is 7.5±3.7 and 5.7±1.8 L/kg, respectively. Absorption On the basis of mass balance studies, at least 92% of a single oral dose of venlafaxine is absorbed, indicating that absorption of venlafaxine is nearly complete. However, the presystemic metabolism of venlafaxine (which primarily forms the active metabolite, ODV) reduces the absolute bioavailability of venlafaxine to 42%±15%. After administration of EFEXOR-XR (150 mg q24 hours), the peak plasma concentrations (Cmax) of venlafaxine (150 ng/mL) and ODV (260 ng/mL) were attained within 6.0±1.5 and 8.8±2.2 hours, respectively. The rate of absorption of venlafaxine from the EFEXOR-XR capsule is slower than its rate of elimination. Therefore, the apparent elimination half-life of venlafaxine following administration of EFEXOR-XR (15±6 hours) is actually the absorption half-life instead of the true disposition half-life (5±2 hours) observed following administration of an immediate-release tablet. When equal doses of venlafaxine, administered either as an immediate- release tablet taken in divided doses or as a modified-release capsule, were taken once a day, the exposure (AUC, area under the concentration curve) to both venlafaxine and ODV was similar for the two treatments, and the fluctuation in plasma concentrations was slightly lower following treatment with the EFEXOR-XR capsule. Therefore, the EFEXOR-XR capsule provides a slower rate of absorption, but the same extent of absorption (i.e., AUC), as the venlafaxine immediate-release tablet. No accumulation of venlafaxine or ODV has been observed during chronic administration in healthy subjects. Distribution The degree of binding of venlafaxine to human plasma proteins is 27% ±2% at concentrations ranging from 2.5 to 2215 ng/mL, and the degree of ODV binding to human plasma proteins is 30%±12% at concentrations ranging from 100 to 500 ng/mL. Protein-binding-induced drug interactions with concomitantly administered venlafaxine are not expected. Following intravenous administration, the steady-state volume of distribution of venlafaxine is 4.4±1.9 L/kg, indicating that venlafaxine distributes well beyond the total body water. Metabolism Following absorption, venlafaxine undergoes extensive pre-systemic metabolism in the liver. The primary metabolite of venlafaxine is ODV, but venlafaxine is also metabolised to N-desmethylvenlafaxine, N,O-didesmethylvenlafaxine, and other minor metabolites. In vitro studies indicate that the formation of ODV is catalysed by CYP2D6 and that the formation of N-desmethylvenlafaxine is catalysed by CYP3A3/4. The results of the in vitro studies have been confirmed in a clinical study with subjects who are CYP2D6-poor and -extensive metabolisers. However, despite the metabolic differences between the CYP2D6-poor and -extensive metabolisers, the total exposure to the sum of the two active species (venlafaxine and ODV) was similar in the two metaboliser groups. Therefore, CYP2D6-poor and -extensive metabolisers can be treated with the same regimen of EFEXOR-XR (see Interactions with Other Drugs, CYP2D6 Inhibitors). Excretion Approximately 87% of a venlafaxine dose is recovered in the urine within 48 hours after a single radio-labelled dose as either unchanged venlafaxine (5%), unconjugated ODV (29%), conjugated ODV (26%), or other minor inactive metabolites (27%), and 92% of the radioactive dose is recovered within 72 hours. Therefore, renal elimination of venlafaxine and its metabolites is the primary route of excretion. Food-Drug Interactions Administration of EFEXOR-XR with food has no effect on the absorption of venlafaxine or on the subsequent formation of ODV. Subject age and sex do not significantly affect the pharmacokinetics of venlafaxine. A 20% reduction in clearance was noted for ODV in subjects over 60 years old; this was probably caused by the decrease in renal function that typically occurs with aging. In some patients with compensated hepatic cirrhosis, the pharmacokinetic disposition of both venlafaxine and ODV was significantly altered. The reduction in both the metabolism of venlafaxine and elimination of ODV resulted in higher plasma concentrations of both venlafaxine and ODV. In patients with moderate to severe impairment of renal function, the total clearance of both venlafaxine and ODV was reduced, and t½ was prolonged. The reduction in total clearance was most pronounced in subjects with creatinine clearance less than 30 mL/min. Clinical Trials Use in Major Depression Three double blind, placebo controlled trials, of up to 12 weeks duration, have examined the clinical efficacy of EFEXOR-XR in the treatment of major depression. One of these studies also incorporated an active comparator, paroxetine. These studies showed EFEXOR-XR to have greater efficacy than both placebo and paroxetine in reducing depression. Use in Generalised Anxiety Disorder Five placebo-controlled trials were conducted to evaluate the efficacy of EFEXOR-XR in the treatment of anxiety. Two trials were eight-week studies, utilizing Efexor-XR doses of 75 mg, 150 mg and 225 mg/day and of 75 mg and 150 mg/day. In one of these, buspirone was found not to be significantly different to placebo or to Efexor- XR. However, Efexor-XR was found to be superior to placebo. Two other trials were the first eight-weeks of two long term studies, utilizing Efexor-XR doses of 75 mg-225 mg/day and of 37.5 mg, 75 mg and 150 mg/day. Four studies demonstrated superiority of Efexor-XR over placebo on at least five of the following efficacy scales: HAM-A total score, the HAM-A psychic anxiety factor, the Hospital Anxiety and Depression (HAD) anxiety subscale, and the CGI severity of illness scale, as well as the HAM-A anxious mood and tension item. Two of these four studies continued for up to six months. These two studies, which utilized Efexor-XR doses of 75 mg-225 mg/day and 37.5 mg, 75 mg and 150 mg/day demonstrated superiority of Efexor-XR over placebo on the HAM-A total score, HAM-A psychic anxiety factor, the HAD anxiety factor, and the CGI severity of illness scale, as well as the HAM-A anxious mood item. The fifth trial was a short-term (8-week) comparison of the efficacy of 2 fixed doses of EFEXOR-XR (75 mg and 150 mg) with placebo and diazepam followed by a comparison of the long-term (6-month) efficacy of EFEXOR-XR and placebo in the prevention of relapse. The most important results were the primary efficacy variables at week 8 using an LOCF analysis. These demonstrated no significant differences between either venlafaxine and placebo, or diazepam and placebo for any of the primary efficacy variables. In view of this failure to demonstrate any effectiveness of either venlafaxine or diazepam over placebo, the long-term outcomes of this study are not of clinical or theoretical value. In conclusion, this study showed no anxiolytic effect of either diazepam or placebo in the short-term (8 week phase). Baseline and Final Mean HAM-A Total and CGI Severity Scores for Placebo-Controlled GAD Studies Study Number ----------- HAM-A Total----------- ----------- CGI Severity --------- Treatment n Baseline Final n Baseline Final 210 (8-week study) Placebo 96 24.1 14.7 96 4.4 3.2 Venlafaxine XR (mg) 75 86 24.7 13.5 86 4.5 3.0 150 81 24.5 12.3 81 4.5 2.9 225 86 23.6 11.9 86 4.4 2.8 214 (8-week study) Placebo 98 23.7 15.4 98 4.3 3.3 Venlafaxine XR (mg) 75 87 23.7 13.0 87 4.2 2.8 150 87 23.0 13.6 87 4.2 3.0 Buspirone 93 23.8 14.3 93 4.2 3.2 218 (6-month study) Placebo 123 24.9 16.2 123 4.4 3.5 Venlafaxine XR (mg) 75-225 115 25.0 11.6 115 4.4 2.7 377 (8-week period) Placebo 96 27.7 15.1 89 4.8 3.2 Venlafaxine XR (mg) 75 181 28.0 12.8 160 4.9 2.9 150 169 28.0 14.2 146 4.9 3.1 epam 89 28.4 13.5 79 4.8 2.9 378 (6-month study) Placebo 129 26.7 15.6 129 4.6 3.2 Venlafaxine XR (mg) 37.5 138 26.6 12.6 138 4.4 2.6 75 130 26.3 10.4 129 4.4 2.4 150 131 26.3 9.5 131 4.6 2.2 Depression Relapse/Recurrence A long-term study of depressed outpatients who had responded to EFEXOR-XR during an initial 8-week open-label treatment phase and were randomly assigned to continuation on EFEXOR-XR or placebo for 6 months demonstrated a significantly lower relapse rate for patients taking EFEXOR-XR compared with those on placebo. In a second long-term study, outpatients with a history of recurrent depression who had responded to EFEXOR (the immediate-release form of venlafaxine) by 8 weeks and maintained improvement during an initial 6-month open-label treatment phase were randomly assigned to maintenance therapy on EFEXOR or placebo for 12 months. Significantly fewer patients taking EFEXOR compared with those on placebo had a reappearance of depression. Social Anxiety Disorder The efficacy of Efexor-XR as a treatment for social anxiety disorder (also known as social phobia) was established in four double-blind, parallel-group, 12-week, multi-centre, placebo-controlled, flexible- dose studies and one double-blind, parallel-group, 6-month, fixed/flexible-dose study in adult outpatients meeting DSM-IV criteria for Social Anxiety Disorder. Patients received doses in a range of 75-225 mg/day. Efficacy was assessed with the Liebowitz Social Anxiety Scale (LSAS). The LSAS measures the relationship of impairment because of social anxiety disorder symptoms by evaluating a patient's fear and avoidance in a broad range of situations (i.e., 13 performance and 11 social interaction situations). Psychometric studies have shown the LSAS to be a valid and reliable measure of social anxiety.1 The LSAS scale has also been shown to be sensitive to differences between active and placebo treatments.2 The results of these trials are presented in the table below. In these five trials, Efexor-XR was significantly more effective than placebo on change from baseline to endpoint on the LSAS total score. Summary of Results for Primary Efficacy Variable in ITT Patients at Final On-Therapy Visit: 12 week and 6 month Variable Study Number No. of Patients Raw baseline Score Adjusted Final On-therapy Score Adjusted Mean Change from Baseline p-value vs Placebo Treatment Group Short-term (12 week) Studies LSAS Study 1 Placebo 138 86.7 69.0 -19.9 Venlafaxine XRa 133 91.1 57.8 -31.0 <0.001 Study 2b Placebo 135 87.4 66.9 -22.1 Venlafaxine XRa 126 90.8 56.3 -32.8 0.003 Study 3 Placebo 132 83.6 64.5 -19.1 Venlafaxine XRa 129 83.2 47.6 -36.0 <0.001 Paroxetinec 128 83.9 48.1 -35.4 <0.001 Study 4 Placebo 144 86.1 64.3 -22.2 Venlafaxine XR 133 86.2 51.5 -35.0 <0.001 Paroxetine 136 87.2 47.3 -39.2 <0.001 Long-term (6 month) Study LSAS Study 5 Placebo 126 89.3 65.6 -23.5 Venlafaxine XR (total)d 238 89.0 51.2 -37.8 <0.001 Venlafaxine XR 75mg 119 91.8 51.0 -38.1 <0.001 Venlafaxine 150-225mg 119 86.2 51.5 -37.6 <0.001 a: Flexible dose range for venlafaxine XR was 75-225mg/day; b: Data shown are for ITT population; c: Flexible dose range for paroxetine was 20-50mg/day; d: Primary treatment group. Abbreviations: ITT = intent to treat; LSAS = Liebowitz Social Anxiety Scale INDICATIONS EFEXOR-XR is indicated for the treatment of: Major depression Generalised anxiety disorder; Social Anxiety Disorder. EFEXOR-XR is also indicated for the prevention of relapse and recurrence of major depression where appropriate. CONTRAINDICATIONS Hypersensitivity to venlafaxine or any excipients in the formulation Concomitant use of venlafaxine and any monoamine oxidase inhibitor- (MAOI) is contraindicated. EFEXOR-XR must not be initiated for at least 14 days after discontinuation of treatment with a MAOI. EFEXOR- XR must be discontinued for at least 7 days before starting treatment with any MAOI -(See PRECAUTIONS - Interactions with other drugs). PRECAUTIONS Use in Patients with Renal Impairment The total daily dose of venlafaxine must be reduced by 25% to 50% for patients with renal impairment with a glomerular filtration rate (GFR) of 10 to 70 mL/min. The total daily dose of venlafaxine must be reduced by 50% in haemodialysis patients. Administration must be withheld until the dialysis session is completed. Use in Patients with Hepatic Impairment The total daily dose of venlafaxine must be reduced by 50% in patients with moderate hepatic impairment. Reductions of more than 50% may be appropriate for some patients. Sustained Hypertension Dose-related increases in blood pressure have been reported in some patients treated with venlafaxine. Among patients treated with 75 to 375 mg per day of EFEXOR-XR in pre- marketing depression studies, 3% (19/705) experienced sustained hypertension [defined as treatment-emergent supine diastolic blood pressure (SDBP) ( 90 mm Hg and ( 10 mm Hg above baseline for 3 consecutive on-therapy visits]. Among patients treated with 37.5 to 225 mg per day of EFEXOR-XR in pre-marketing GAD studies, 0.5% (5/1011) experienced sustained hypertension. Experience with the immediate-release venlafaxine showed that sustained hypertension was dose-related, increasing from 3 to 7% at 100 to 300 mg per day to 13% at doses above 300 mg per day. An insufficient number of patients received mean doses of EFEXOR-XR over 300 mg per day to fully evaluate the incidence of sustained increases in blood pressure at these higher doses. In placebo-controlled pre-marketing depression studies with EFEXOR- XR 75 to 225 mg per day, a final on-drug mean increase in supine diastolic blood pressure (SDBP) of 1.2 mm Hg was observed for EFEXOR- XR treated patients compared with a mean decrease of 0.2 mm Hg for placebo-treated patients. In placebo-controlled pre-marketing GAD studies with EFEXOR-XR 37.5 to 225 mg per day up to 8 weeks or up to 6 months, a final on-drug mean increase in SDBP of 0.3 mm Hg was observed for EFEXOR-XR treated patients compared with a mean decrease of 0.9 and 0.8 mm Hg, respectively, for placebo-treated patients. In pre-marketing Social Anxiety Disorder studies up to 12 weeks, the final on-therapy mean change from baseline in SDBP was small - an increase of 0.78 mmHg, compared to a decrease of 1.41 mmHg in placebo-treated patients. In a 6-month study, the final on- therapy mean increase from baseline in SDBP with EFEXOR-XR 150 to 225 mg was 1.49 mmHg. The increase was significantly different from the 0.6 mmHg decrease with placebo and the 0.2 mmHg decrease with EFEXOR-XR 75 mg In pre-marketing depression studies, 0.7% (5/705) of the EFEXOR-XR treated patients discontinued treatment because of elevated blood pressure. Among these patients, most of the blood pressure increases were in a modest range (12 to 16 mm Hg, SDBP). In pre-marketing GAD studies up to 8 weeks and up to 6 months, 0.7% (10/1381) and 1.3% (7/535) of the EFEXOR-XR treated patients, respectively, discontinued treatment because of elevated blood pressure. Among these patients, most of the blood pressure increases were in a modest range (12 to 25 mm Hg, SDBP up to 8 weeks; 8 to 28 mm Hg up to 6 months). Sustained increases of SDBP could have adverse consequences. Therefore it is recommended that patients receiving EFEXOR-XR have regular monitoring of blood pressure. For patients who experience a sustained increase in blood pressure while receiving venlafaxine, either dose reduction or discontinuation should be considered. Increase in Serum Cholesterol Clinically relevant increases in serum cholesterol were recorded in 5.3% of EFEXOR immediate release tablet-treated patients and 0.0% of placebo-treated patients for at least 3 months in placebo-controlled clinical trials. Treatment with EFEXOR-XR for up to 12 weeks in pre-marketing placebo- controlled depression trials was associated with a mean final on- therapy increase in serum cholesterol concentration of approximately 0.039 mmol/L (1.5 mg/dL). EFEXOR-XR treatment for up to 8 weeks and up to 6 months in pre-marketing placebo-controlled GAD trials was associated with mean final on-therapy increases in serum cholesterol concentration of approximately 0.026 mmol/L (1.0 mg/dL) and 0.059 mmol/L (2.3 mg/dL), respectively. In the 12 week Social Anxiety Disorder studies, small mean increases in fasting levels of total cholesterol (0.20 mmol/L, 4%) were seen in the EFEXOR-XR-treated group at the final on-therapy evaluation; the increases were significantly different from the changes in the placebo group. In a 6-month study, the final on-therapy mean increase in total cholesterol was higher (0.32mmol/L, 7%) in the EFEXOR-XR 150 to 225 mg group; however the total cholesterol value was slightly decreased (0.01mmol/L) for the EFEXOR-XR group. There were also significant mean increases from baseline in LDL, but not HDL for the EFEXOR-XR 150 to 225 mg group. The final on-therapy increase of 0.213 mmol/L from baseline in LDL with EFEXOR-XR 150 to 225 mg was significantly different from the small decrease with placebo (0.079 mmol/L) and the negligible increase with EFEXOR-XR 75mg (0.006 mmol/L). Measurement of serum cholesterol levels should be considered during long-term treatment. Hyponatraemia Cases of hyponatraemia, and/or the Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH) may occur with venlafaxine, usually in volume-depleted or dehydrated patients, including elderly patients and in patients taking diuretics. These have resolved on discontinuation of the drug. Caution is advised in administering EFEXOR-XR to patients with diseases or conditions that could affect haemodynamic responses or metabolism. Myocardial Infarction and Unstable Heart Disease Venlafaxine has not been evaluated in patients with a recent history of myocardial infarction or unstable heart disease. Therefore it should be used with caution in these patients. Patients with these diagnoses were systematically excluded from any clinical studies during the product's trials. Evaluation of the electrocardiograms for 769 patients who received immediate release EFEXOR in 4 to 6-week double blind, placebo- controlled trials showed that the incidence of trial-emergent conduction abnormalities did not differ from that with placebo. The electrocardiograms for patients who received EFEXOR-XR or placebo in the depression GAD and Social Anxiety Disorder trials were analysed. The mean change from baseline in corrected QT interval (QTc) for EFEXOR-XR treated patients in depression studies was increased relative to that for placebo-treated patients (increase of 4.7 msec for EFEXOR-XR and decrease of 1.9 msec for placebo). The mean change from baseline QTc for EFEXOR-XR treated patients in the GAD studies did not differ significantly from placebo. The final on-therapy mean increase from baseline in QTc (3 msec) was significant for Efexor-XR treated patients in the Social Anxiety Disorder short-term studies. In the 6 month study, the final on-therapy mean increase from baseline in QTc with EFEXOR-XR 150 to 225 mg (3 msec) was significant, but the increase was not significantly different from the small mean increase (0.5 msec) with placebo. The value for EFEXOR-XR 75mg was a 0.05 msec decrease. Increases in heart rate may occur, particularly with higher doses. Therefore caution is advised in patients whose underlying conditions may be compromised by increases in heart rate. The mean change from baseline in heart rate for EFEXOR-XR treated patients in both the GAD and depression studies was significantly higher than for placebo (a mean increase of 3-4 beats per minute for EFEXOR-XR and 0-1 beat per minute for placebo in the GAD and depression studies respectively). In the pooled short-term Social Anxiety Disorder studies, the final on-therapy mean increase from baseline in heart rate with EFEXOR-XR was 5 beats per minute. In the 6 month study, the final on-therapy mean increases from baseline in heart rate were significant with EFEXOR-XR 75 (2 beats per minute) and EFEXOR-XR 150 to 225 mg (6 beats per minute); however only the increase with the higher dose was significantly different from the small increase with placebo (0.4 beats per minute). The clinical significance of these changes is unknown. Mydriasis Mydriasis may occur in association with venlafaxine. It is recommended that patients with raised intra-ocular pressure or patients at risk for acute narrow-angle glaucoma should be closely monitored. Abrupt Discontinuation of Efexor-XR Discontinuation effects are well known to occur with antidepressants. Discontinuation symptoms have been assessed both in patients with depression and in those with anxiety. Abrupt discontinuation, dose reduction, or tapering of venlafaxine at various doses has been found to be associated with the appearance of new symptoms, the frequency of which increased with increased dose level and with longer duration of treatment. Symptoms reported included agitation, anorexia, anxiety, confusion, dry mouth, fatigue, paraesthesias, vertigo, hypomania, nausea, vomiting, dizziness, convulsion, headache, diarrhoea, sleep disturbance, insomnia, somnolence, sweating and nervousness. Where such symptoms occurred, they were usually self-limiting, but in a few patients lasted for several weeks. There is also a report of a withdrawal syndrome, confirmed by two challenges in a 32-year-old woman who had received venlafaxine 300 mg daily for 8 months. It is, therefore, recommended that the dosage of EFEXOR-XR be tapered gradually and the patient monitored. The period required for discontinuation may depend on the dose, duration of therapy and the individual patient (See DOSAGE AND ADMINISTRATION). Altered Weight Weight changes, either losses or gains, do not appear to present a clinically important feature of venlafaxine treatment. Clinically significant weight gain or loss was seen in less than 1% of patients treated with venlafaxine during clinical trials. A dose-dependent weight loss (mean loss <1 kg) was noted in some patients treated with venlafaxine during the first few months of venlafaxine treatment. After month 9, the mean weight began to increase slightly but significantly, an effect often seen with tricyclic antidepressant therapy. Significant weight loss (> 7 kg) was seen in 6 (0.3%) of 2,181 patients, compared to no patients treated with placebo and 0.2% of patients treated with a comparative antidepressant. The safety and efficacy of venlafaxine therapy in combination with weight loss agents, including phentermine, have not been established. Co-administration of EFEXOR-XR and weight loss agents is not recommended. EFEXOR-XR is not indicated for weight loss alone or in combination with other products. Suicide The risk of suicide attempt must be considered in all depressed patients. Prescriptions for EFEXOR-XR should be written for the smallest quantity of capsules consistent with good patient management in order to reduce the possibility of overdosage. Seizures Seizures may occur with venlafaxine therapy. EFEXOR-XR, as with all antidepressants, should be introduced with care, in patients with a history of seizure disorders. EFEXOR-XR should be discontinued in any patient who develops seizures. Activation of Mania/Hypomania Mania/hypomania may occur in a small proportion of patients with mood disorders treated with antidepressants, including venlafaxine. Venlafaxine should be used cautiously in patients with a history of mania. Skin/Allergic Reactions Patients should be advised to notify their physician if they develop a rash, hives, or related allergic phenomena Skin and Mucous Membrane Bleeding The risk of skin and mucous membrane bleeding may be increased in patients taking venlafaxine, particularly if predisposed to such events. Venlafaxine should be used cautiously in patients predisposed to bleeding at these sites. Effects on Cognitive and Motor Performance Although venlafaxine has been shown not to affect psychomotor, cognitive or complex behaviour performance in healthy volunteers, any psychoactive medication may impair judgment, thinking or motor skills, and patients should be cautioned about operating hazardous machinery, including automobiles, until they are reasonably certain that the treatment does not affect them adversely. Physical and Psychological Dependence Clinical studies have shown no evidence of drug-seeking behaviour, development of tolerance, or dose escalation over time among patients taking venlafaxine. Consequently, physicians should carefully evaluate patients for a history of drug abuse and follow such patients closely observing them for signs of misuse or abuse of venlafaxine (e.g. development of tolerance, increase in dose, drug- seeking behaviour) (see PHARMACOLOGY). Use in Elderly Patients No overall differences in effectiveness or safety were observed between elderly (aged 65 years and older) and younger patients. EFEXOR-XR does not appear to pose any exceptional safety problems for healthy elderly patients. Effectiveness in elderly patients with social anxiety disorder has not been established. Paediatric Use Safety and effectiveness in individuals below 18 years of age have not been established. Efexor-XR should not be used in such patients. As with adults, decreased appetite, weight loss, increased blood pressure and increased serum cholesterol have been observed in children and adolescents aged 6 to 17 years. In paediatric clinical trials, there were increased reports of hostility and, especially in major depressive disorder, suicide- related adverse events such as suicidal ideation and self-harm. Carcinogenesis, Mutagenesis, Impairment of Fertility Evidence of impairment of fertility was not noted in preclinical toxicology studies. Venlafaxine was given by oral gavage to mice and rats for 18 months and 24 months respectively, at dosages up to 120 mg/kg/day. There were no clear drug-related oncogenic effects in either species. In these studies, animal exposure to the main human metabolite ODV was less, and exposure to venlafaxine was more than would be expected in humans taking the recommended therapeutic and maximum doses. There was no evidence of gene mutation or chromosomal change in a series of genotoxicity assays using venlafaxine and the main human metabolite ODV. Signs of pharmacologic toxicity were seen in paternal and maternal rats given venlafaxine doses of 30 and 60 mg/kg/day, but no adverse effect was noted in fertility or general reproductive performance. Decreased foetal size and pup weight at birth with 60 mg/kg/day may be correlated with maternal toxicity. Use During Pregnancy Category: B2 The safety of venlafaxine in human pregnancy has not been established. There are no adequate and well-controlled studies in pregnant women. Because animal reproductive studies are not always predictive of human response, this medication should be used during pregnancy only if clearly needed. Patients should be advised to notify their physician if they become pregnant or intend to become pregnant during therapy. If venlafaxine is used until or shortly before birth, discontinuation effects in the newborn should be considered. In a rat teratology study, venlafaxine was given orally at dosages up to 80 mg/kg/day (approximately 11 times the maximum recommended human dose). Foetotoxicity evidenced by growth retardation was slightly increased at 80 mg/kg/day, an effect which may be related to maternal toxicity at this dose level. Foetal survival and morphologic development were not affected. In another teratology study, rabbits were given venlafaxine dosages up to 90 mg/kg/day. Foetotoxicity evidenced by resorption and foetal loss was slightly increased at 90 mg/kg/day; (approximately 12 times the maximum recommended human dose). These effects could be correlated with maternal toxicity. No venlafaxine-associated teratogenic effect was noted in either species at any dosage, though there was an increased incidence of 'W'-shaped apex of the heart in the rabbit study. In these studies, animal exposure to the main human metabolite ODV was less, and estimated exposure to venlafaxine was approximately 6-fold more than would be expected in humans taking the recommended therapeutic and maximum doses. In rats, estimated exposure to venlafaxine was more than the expected human exposure. No teratogenic effect was seen. In a perinatal toxicity study in rats after oral dosing of dams with 30 mg/kg or more, decreased pup survival following birth was observed. This effect is secondary to treatment-decreased maternal care, and is also seen with other antidepressants. Use During Lactation Venlafaxine and/or its metabolites are secreted in milk of lactating rats at concentrations higher than those found in the plasma of the dam. Venlafaxine and its metabolites have been shown to pass into human milk. The total dose of venlafaxine and O-desmethylvenlafaxine ingested by breast fed infants can be as high as 9.2% of maternal intake. Therefore, the use of EFEXOR-XR in nursing women cannot be recommended. Exposed infants should be observed closely. Interactions with other Drugs Venlafaxine and ODV are 27% and 30% bound to plasma proteins respectively, therefore interactions due to protein binding of venlafaxine and the major metabolite are not expected. Monoamine oxidase inhibitors Concomitant use with EFEXOR is contraindicated. Irreversible MAOI Inhibitors Severe adverse reactions have been reported in patients who have recently been discontinued from a MAOI and started on venlafaxine, or have recently had venlafaxine therapy discontinued prior to initiation of a MAOI or when these two agents are co-administered. Reactions have included tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome and/or serotonergic syndrome, seizures, and death. Do not use EFEXOR in combination with a MAOI or within at least 14 days of discontinuing MAOI treatment. Allow at least 7 days after stopping EFEXOR-XR before starting a MAOI (see CONTRAINDICATIONS). Reversible MAOI Inhibitors EFEXOR should not be administered concomitantly with moclobemide. There are no clinical trials to support the recommendation of a specific time between discontinuing treatment with the reversible MAOI, moclobemide and initiating EFEXOR therapy or switching to moclobemide. Given the risk for adverse reactions described for irreversible MAOIs (see above), an adequate washout period should be ensured when switching a patient between EFEXOR and moclobemide. The appropriate washout period should take into account the pharmacological properties of venlafaxine and moclobemide and the clinician's assessment of the individual patient. Based on the half- lives of moclobemide, venlafaxine and ODV, the minimum washout period should be 24 hours when switching from moclobemide to EFEXOR and 7 days when switching from EFEXOR to moclobemide. Warfarin There have been reports of increases in prothrombin time, partial thromboplastin time, or INR when venlafaxine was given to patients receiving warfarin therapy. Alcohol Venlafaxine has not been shown to increase the impairment of mental and motor skills caused by ethanol. However, as with all CNS active drugs, patients should be advised to avoid alcohol consumption while taking EFEXOR. Cimetidine Cimetidine inhibited the first-pass metabolism of venlafaxine but had no apparent effect on the formation or elimination of ODV, which is present in much greater quantity in the systemic circulation. No dosage adjustment seems necessary when EFEXOR is co-administered with cimetidine. However, for elderly patients or patients with hepatic dysfunction, the interaction could potentially be more pronounced and for such patients clinical monitoring is indicated when EFEXOR is administered with cimetidine. epam. The pharmacokinetic profiles of venlafaxine and ODV were not altered when venlafaxine and diazepam were administered together to healthy volunteers. Venlafaxine had no effect on the pharmacokinetics of diazepam or affect the psychomotor and psychometric effects induced by diazepam. Lithium The steady-state pharmacokinetics of venlafaxine and ODV are not affected when lithium is co-administered. Venlafaxine also has no effect on the pharmacokinetics of lithium. (See also CNS Active drugs.) Haloperidol Venlafaxine administered under steady-state conditions (75 mg twice daily) to 24 healthy subjects decreased total oral clearance (Cl/F) of a single 2 mg dose of haloperidol by 42%, which resulted in a 70% increase in haloperidol AUC. In addition, the haloperidol Cmax increased 88% when co-administered with venlafaxine, but the haloperidol elimination half-life (t½) was unchanged. The mechanism explaining this finding is unknown. Imipramine Venlafaxine did not affect the CYP2D6-mediated 2-hydroxylation of imipramine or its active metabolite, desimipramine, which indicates that venlafaxine does not inhibit the CYP2D6 isoenzyme. However, the renal clearance of 2-hydroxydesimipramine was reduced with co- administration of venlafaxine. Imipramine partially inhibited the CYP2D6-mediated formation of ODV, however, the total concentrations of active compounds (venlafaxine plus ODV) was not affected with imipramine administration. Additionally, in a clinical study involving CYP2D6-poor and - extensive metabolisers, the total sum of the two active species (venlafaxine and ODV) was similar in the two metaboliser groups. Therefore, no dosage adjustment is expected when venlafaxine is co- administered with a CYP2D6 inhibitor. However, desipramine AUC, Cmax, and Cmin increased by about 35% in the presence of venlafaxine. There was an increase of 2-OH-desipramine AUC by 2.5 to 4.5 fold. The clinical significance of this finding is unknown. Risperidone Venlafaxine increased risperidone AUC by 32% but did not significantly alter the pharmacokinetic profile of the total active moiety (risperidone plus 9-hydroxy-risperidone). The clinical significance of this interaction is unknown. Indinavir A pharmacokinetic study with indinavir has shown a 28% decrease in AUC and a 36% decrease in Cmax for indinavir. Indinavir did not affect the pharmacokinetics of venlafaxine and ODV. The clinical significance of this interaction is unknown. Antihypertensive and Hypoglycaemic Agents Retrospective analysis of study events occurring in patients taking venlafaxine concurrently with antihypertensive or hypoglycaemic agents in clinical trials provided no evidence suggesting incompatibility between treatment with venlafaxine and treatment with either antihypertensive or hypoglycaemic agents. CNS Active Drugs Based on the known mechanism of action of venlafaxine and the potential for serotonin syndrome, caution is advised when EFEXOR is co-administered with other drugs that may affect the serotonergic neurotransmitter systems (such as triptans, SSRIs or lithium). No information is available on the use of EFEXOR in combination with opiates. There have been reports of elevated clozapine levels in association with adverse events including seizures, following the administration of venlafaxine. As with other antidepressants, co-administration of EFEXOR and products containing Hypericum perforatum (St. 's Wort) is not recommended due to possible pharmacodynamic interactions. Drugs that Inhibit Cytochrome P450 Isoenzymes CYP2D6 Inhibitors In vitro and in vivo studies indicate that venlafaxine is metabolised predominantly to ODV by CYP2D6, the isoenzyme that is responsible for the genetic polymorphism seen in the metabolism of many antidepressants. Therefore the potential exists for a drug interaction between drugs that inhibit CYP2D6-mediated metabolism (such as amiodarone and quinidine) and venlafaxine. Drug interactions that reduce the metabolism of venlafaxine to ODV potentially increase the plasma concentrations of venlafaxine and lower the concentration of the active metabolite. The concomitant use of venlafaxine with drug treatment(s) that potentially inhibits both CYP2D6 and CYP3A4, the primary metabolising enzymes for venlafaxine, has not been studied. Therefore caution is advised if a patient's therapy includes venlafaxine and any agent(s) that produces simultaneous inhibition of these two enzyme systems. CYP3A4 Inhibitors In vitro studies indicate that venlafaxine is likely metabolised to a minor, less active metabolite, N-desmethylvenlafaxine, by CYP3A4. Because CYP3A4 is a minor pathway relative to CYP2D6 in the metabolism of venlafaxine, the potential for a clinically significant drug interaction between inhibitors of CYP3A4-mediated metabolism (such as erythromycin, fluconazole and grapefruit juice) and venlafaxine is small. Drugs Metabolised by Cytochrome P450 Isoenzymes In vitro studies indicate that venlafaxine is a relatively weak inhibitor of CYP2D6 and that venlafaxine does not inhibit CYP1A2, CYP2C9 or CYP3A4. Some of these findings have been confirmed with drug interaction studies between venlafaxine and imipramine (metabolised by CYP2D6) and diazepam (metabolised by CYP2C19). Therefore, EFEXOR-XR is not expected to interact with other drugs metabolised by these isoenzymes. Electroconvulsive Therapy There are no clinical data establishing the benefit of EFEXOR-XR combined with electroconvulsive therapy. Effects on Laboratory tests No interference on laboratory tests by venlafaxine is known. ADVERSE REACTIONS Adverse reactions are listed in the following table in CIOMS frequency categories: Common: = 1%; Uncommon: = 0.1% and <1%; Rare: = 0.01% and <0.1%; Very rare: <0.01%. Body System Adverse Reactions Body As A Whole Common: Asthenia/fatigue. Uncommon: Photosensitivity reaction. Very rare: Anaphylaxis. Cardiovascular Common: Hypertension, vasodilatation (mostly hot flashes/flushes). Uncommon: Hypotension, postural hypotension, syncope, tachycardia. Very rare: QT prolongation, ventricular fibrillation, ventricular tachycardia (including torsade de pointes). Digestive Common: Appetite decreased, constipation, nausea, vomiting. Uncommon: Bruxism. Undetermined Frequency: Pancreatitis. Haematological/Lymphatic Uncommon: Ecchymosis, mucous membrane bleeding. Rare: Prolonged bleeding time, thrombocytopenia. Undetermined Frequency: Blood dyscrasias (including agranulocytosis, aplastic anemia, neutropenia and pancytopenia) Metabolic/Nutritional Common: Serum cholesterol increased (particularly with prolonged administration and with higher doses), weight loss. Uncommon: Abnormal liver function tests, hyponatraemia, weight gain. Rare: Hepatitis, syndrome of inappropriate antidiuretic hormone secretion (SIADH). Undetermined Frequency: Prolactin increased. Musculoskeletal Undetermined Frequency: Rhabdomyolysis. Nervous Common: Abnormal dreams, decreased libido, dizziness, dry mouth, increased muscle tonus, insomnia, nervousness, paraesthesia, sedation, tremor. Uncommon: Apathy, hallucinations, myoclonus. Rare: Convulsion, manic reaction, neuroleptic malignant syndrome (NMS), serotonergic syndrome. Undetermined Frequency: Agitation, delirium, extrapyramidal reactions (including dystonia, and dyskinesia), tardive dyskinesia. Respiratory Common: Yawning. Undetermined Frequency: Pulmonary eosinophilia. Skin Common: Sweating (including Night Sweats). Uncommon: Rash, alopecia. Very Rare: Erythema multiforme, s- syndrome. Special Senses Common: Abnormality of accommodation, mydriasis, visual disturbance. Uncommon: Altered taste sensation. Undetermined Frequency: Tinnitus. Urogenital Common: Abnormal ejaculation/orgasm (males), anorgasmia, erectile dysfunction, urination impaired (mostly hesitancy) Uncommon: Abnormal orgasm (females), menorrhagia, urinary retention, proteinuria. Discontinuation effects are well known to occur with antidepressants, and it is therefore recommended that the dosage is tapered gradually and the patient monitored (see DOSAGE AND ADMINISTRATION). The following symptoms have been reported in association with abrupt discontinuation or dose-reduction, or tapering of treatment: hypomania, anxiety, agitation, nervousness, confusion, insomnia or other sleep disturbances, fatigue, somnolence, paraesthesia, dizziness, convulsion, vertigo, headache, sweating, dry mouth, anorexia, diarrhoea, nausea, and vomiting. The majority of discontinuation reactions are mild and resolve without treatment. In the Social Anxiety Disorder pooled short-term studies, the most common taper/post-study-emergent adverse events were dizziness (13%), nausea (7%), insomnia (3%), nervousness (3%) and asthenia (2%). In the 6-month study, the most common taper/post-study treatment emergent adverse events were dizziness (21% and 16%) and nausea (7% and 10%) for EFEXOR-XR 75 mg and EFEXOR-XR 150-225 mg, respectively. Paediatric Patients (see PRECAUTIONS - Paediatric Use) In general, the adverse reaction profile of venlafaxine in placebo- controlled clinical trials in children and adolescents (aged 6 to 17) was similar to that seen for adults. As with adults, decreased appetite, weight loss, increased blood pressure and increased serum cholesterol were observed. Additionally, the following adverse reactions were observed: abdominal pain, agitation, dyspepsia, ecchymosis, epistaxis and myalgia. In paediatric clinical trials, there were increased reports of hostility and, especially in major depression, suicide-related adverse events such as suicidal ideation and self-harm. DOSAGE AND ADMINISTRATION Usual Dose The usual recommended dose for the treatment of major depression, generalised anxiety disorder or social anxiety disorder is 75 mg per day given once daily. After two weeks, the dose may be increased to 150 mg per day given once daily if further clinical improvement is required. If needed, this can be increased up to 375 mg given once daily. Dose increments should be made at intervals of approximately 2 weeks or more, but not less than 4 days. Antidepressant activity with the 75 mg dose was observed after 2 weeks of treatment and anxiolytic activity was observed after one week. It is recommended that EFEXOR-XR be taken with food. Each capsule should be swallowed whole with fluid. Do not divide, crush, chew or place the capsule in water. EFEXOR-XR should be administered once daily, at approximately the same time either in the morning or in the evening. Depressed patients who are currently being treated at a therapeutic dose with immediate-release venlafaxine may be switched to EFEXOR-XR or vice versa at the nearest equivalent dose (mg/day). However, individual dosage adjustments may be necessary. Patients with Renal or Hepatic Impairment Patients with renal and/or hepatic impairment should receive lower doses of EFEXOR-XR. It may be necessary to initiate treatment in these patients with immediate-release venlafaxine tablets. Patients whose glomerular filtration rate (GFR) is less than 30 mL/min should have their dosage reduced by 50%. Haemodialysis clearances of both venlafaxine and ODV in humans are low. Nonetheless, it is recommended that the daily dose of EFEXOR-XR be withheld from patients who require dialysis treatment until after completion of the dialysis treatment. Patients with moderate hepatic impairment should also have their dosage reduced by 50%. Further reductions in dosage should be considered for patients with more severe degrees of hepatic impairment. Elderly Patients No adjustment in the usual dose is recommended for elderly patients solely because of their age. As with any antidepressant, however, caution should be exercised in treating the elderly. When individualising the dosage, extra care should be taken when increasing the dose. Maintenance/Continuation/Extended Treatment The physician should periodically re-evaluate the usefulness of long- term EFEXOR-XR treatment for the individual patient. It is generally agreed that acute episodes of major depression require several months or longer of sustained pharmacological therapy. Whether the dose of antidepressant needed to induce remission is identical to the dose needed to maintain and/or sustain euthymia is unknown. Usually, the dosage for prevention of relapse or for prevention of recurrence of a new episode is similar to that used during initial treatment. Patients should be regularly re-assessed in order to evaluate the benefit of long-term therapy. In Social Anxiety Disorder, continuing therapeutic benefit has been established for periods of up to 6 months. The need for continuing medication in patients with Social Anxiety Disorder who improve with EFEXOR-XR treatment should be periodically assessed. Discontinuing EFEXOR-XR When EFEXOR-XR at a dose of 75 mg/day or greater has been administered for more than 1 week is stopped, it is generally recommended that the dose be tapered gradually to minimise the risk of discontinuation symptoms. Patients who have received EFEXOR-XR for 6 weeks or more should have their dose tapered gradually over at least a 2-week period. To facilitate tapering below 75 mg of Efexor- XR, physicians may consider switching some patients from 75 mg of Efexor-XR once daily to 37.5 mg venlafaxine immediate-release tablets twice daily, and then to 37.5 mg venlafaxine immediate- release tablets once daily (see also Usual Dosage above). The period required for tapering may depend on the dose, duration of therapy, and the individual patient. Patients should be advised to consult their physician before abruptly discontinuing EFEXOR-XR. OVERDOSAGE In managing overdosage, consider the possibility of multiple medication involvement. The physician should consider contacting a poison control centre on the treatment of any overdose. (See PRECAUTIONS - Interactions with other drugs). During pre-marketing trials, most patients who have overdosed with venlafaxine were asymptomatic. Of the remainder, somnolence was the most commonly reported symptom. Mild sinus tachycardia and mydriasis have also been reported. There were no reports of seizures, respiratory distress, significant cardiac disturbances, or significant laboratory test result abnormalities among any of the cases reported to date. However, seizures and respiratory distress occurred in one patient in an on-going study who ingested an estimated 2.75g of venlafaxine with naproxen and thyroxine. Generalised convulsions and coma resulted and emergency resuscitation was required. Recovery was good without sequelae. In post-marketing experience, electrocardiogram changes (e.g. prolongation of QT interval, bundle branch block, QRS prolongation), sinus and ventricular tachycardia, bradycardia, hypotension, vertigo, change in level of consciousness (ranging from somnolence to coma), and seizures have been reported in association with overdosage of venlafaxine, either alone or in combination with other drugs and/or alcohol. Such events are rare and usually resolved spontaneously. Also from post-marketing experience, there have been reports of fatalities in patients taking overdoses of venlafaxine, predominantly in combination with alcohol and/or other drugs. Management of Overdosage General supportive and symptomatic measures are recommended. Ensure an adequate airway, oxygenation and ventilation. Cardiac rhythm and vital signs must be monitored. Administration of activated charcoal may also limit drug absorption. Where there is a risk of aspiration, induction of emesis is not recommended. No specific antidotes for venlafaxine are known. Forced diuresis, dialysis, haemoperfusion and exchange transfusion are unlikely to be of benefit. Venlafaxine and ODV are not considered dialyzable because haemodialysis clearance of both compounds is low. PRESENTATION EFEXOR-XR is available for oral use as opaque peach (75 mg) or opaque dark orange (150 mg) modified release capsules with a 'W' and strength printed in red or white, respectively. EFEXOR-XR is packed in blister packs in pack sizes of 7 and 28. MEDICINE CLASSIFICATION PRESCRIPTION ONLY MEDICINE STORAGE Store below 30°C. NAME AND ADDRESS Wyeth (NZ) Limited 15B Vestey Drive, Mt Wellington, AUCKLAND Phone: (09) 573 5100 ®Registered Trade mark Date of preparation: 9 December 2003 > Hi, I'm new. I haven't read much of the board yet, but I thought I > would post the link to the ACNP Task Force " PRELIMINARY REPORT OF THE > TASK FORCE ON SSRIs AND SUICIDAL BEHAVIOR IN YOUTH " > > http://www.acnp.org/exec_summary.pdf > > Please note that members of the task force are also the researchers > who did some of the original studies that were reviewed. Also check > the drug company connections of the task force members listed in the > final pages. > > I would also like to point out the the single most effective and > safest treatment for depression has consistently been proven by the > drug companies clinical double blind studies to be the placebo. In > most (all?) cases, the studied medication out perform the placebo by > less than 20%, often in the 5-10% range while the improvement rate for > the placebo was consistently above 35%, in at least one case as high > as 60%. The more the researchers refine the definition of improvement > in depressive symptoms so that the drug scores higher, the placebo > also scores higher. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 25, 2004 Report Share Posted January 25, 2004 You have seen the Effexor " Dear Doctor " letter, haven't you? Wyeth not only now has that information contained in the Effexor prescribing information/insert/label (need to learn what term you all use here), they sent a letter to doctors in the U.S. and Canada CLEARLY warning them of this. Guess I lot of doctors don't read their mail........ Effexor " Dear Doctor " letter. www.effexor.com/pdf/Wyeth_HCP.pdf The in an artilce about SSRIs in the British newspaper, The Guardian, a reporter wrote that according to a researcher he spoke to said " hostility " can refer to homicidal behavior. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 25, 2004 Report Share Posted January 25, 2004 You have seen the Effexor " Dear Doctor " letter, haven't you? Wyeth not only now has that information contained in the Effexor prescribing information/insert/label (need to learn what term you all use here), they sent a letter to doctors in the U.S. and Canada CLEARLY warning them of this. Guess I lot of doctors don't read their mail........ Effexor " Dear Doctor " letter. www.effexor.com/pdf/Wyeth_HCP.pdf The in an artilce about SSRIs in the British newspaper, The Guardian, a reporter wrote that according to a researcher he spoke to said " hostility " can refer to homicidal behavior. Quote Link to comment Share on other sites More sharing options...
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