Common Causes of Nausea and Vomiting and Treatment Reviewed

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Common Causes of Nausea and Vomiting and Treatment Reviewed

http://www.medscape.com/viewarticle/559665?sssdmh=dm1.286149 & src=nldne

News Author: Emma Hitt, PhD

Release Date: July 12, 2007

July 12, 2007 — In a review article in the July 1 issue of American

Family Physician, Scorza, MD, and colleagues from the Dewitt Army

Community Hospital in Fort Belvoir, Virginia, describe an approach to

evaluating common causes of nausea and vomiting and briefly review

treatment options.

According to the authors, the significant causes of nausea and vomiting

include iatrogenic causes, toxicity, infectious causes, gastrointestinal

disorders, and central nervous system or psychiatric conditions.

Among iatrogenic causes, chemotherapeutic agents are the most well

known. Infectious and toxic causes are usually self-limiting and include

viral gastroenteritis as well as bacteria and their toxins.

Gastrointestinal disorders are often caused by an inflammatory process,

such as appendicitis, cholecystitis, or pancreatitis, or may be caused

by obstruction or motility problems. Central nervous system or

psychiatric causes include increases in intracranial pressure, migraine,

and emotional or physical stressors.

" Pregnancy is the most common endocrinologic cause of nausea and

vomiting and must be considered in any woman of childbearing age, " the

authors point out.

The authors review the 3-step process for evaluating nausea and vomiting

recommended by the American Gastroenterological Association. The 3

recommended steps are as follows:

* Recognize and correct symptoms, such as dehydration or

electrolyte abnormalities.

* Try to identify the underlying cause and provide specific therapy.

* Use empiric therapy if no cause can be identified.

" Diagnostic tests should be ordered only when based on clinical

suspicion, " the authors suggest. " Most of the time, a history and

physical examination can identify the cause. If all organic,

gastrointestinal, and central causes of nausea and vomiting have been

explored, psychogenic vomiting should be considered, " they add. A

detailed algorithm for the evaluation of nausea and vomiting adapted

from an American Gastroenterological Association medical position

statement on nausea and vomiting is provided in the article.

With respect to treatment, the primary goal is " a careful assessment of

fluid and electrolyte status with appropriate replacement, " Dr. Scorza

and colleagues suggest. A low-fat or liquid diet may be prescribed.

Targeted therapy should be given when a specific cause is identified,

but empiric therapy should be administered in the event that the cause

remains unknown. " It is reasonable to begin with a trial of a

phenothiazine, such as prochlorperazine. "

Therapies for known etiologies of nausea and vomiting include the following:

* ondansetron/dexamethasone for acute chemotherapy-induced nausea

and vomiting and metoclopramide/dexamethasone for delayed

chemotherapy-induced nausea and vomiting;

* tricyclic antidepressants for adults with cyclic vomiting syndrome;

* supportive treatment and possible gastric pacing for

gastroparesis; and

* droperidol/dexamethasone or ondansetron for postoperative nausea

and vomiting.

During pregnancy, prochlorperazine, chlorpromazine, metoclopramide, and

methylprednisolone are recommended for hyperemesis gravidarum;

meclizine, promethazine, electrolyte replacement, and thiamine

supplementation are recommended for morning sickness.

Am Fam Physician. 2007;76:76-84.

Clinical Context

Nausea and vomiting are common ailments had by many individuals. Nausea

is defined as the unpleasant, painless sensation that one may

potentially vomit. Vomiting involves the forceful expulsion of stomach

contents through involuntary muscular contractions. The causes of nausea

and vomiting include iatrogenic, toxic, infectious causes;

gastrointestinal disorders; and central nervous system or psychiatric

conditions. Most infections are self-limiting. Most medications can

cause nausea and vomiting; iatrogenic causes are resolved by removing

the offending agent. Gastrointestinal etiologies include obstruction,

functional disorders, and organic diseases. Central nervous system

etiologies are related to conditions that increase intracranial pressure

and cause other neurologic signs. Psychiatric diagnoses such as anorexia

nervosa, bulimia nervosa, depression, and anxiety should be considered.

This article reviews the common and significant causes of nausea and

vomiting, offers an approach to evaluation, and provides a brief

overview of treatment options.

Study Highlights

* The American Gastroenterological Association suggests a 3-step

approach to the initial evaluation of nausea and vomiting.

* The first step is to recognize and correct any consequences of

the symptoms, such as dehydration and electrolyte abnormalities.

* The second step is to try to identify the underlying cause and

provide specific therapies:

o The cause of most acute nausea and vomiting can be

determined from the history and physical examination; diagnostic tests

should be ordered based on clinical suspicion.

o Symptom duration should be determined because the

differential diagnoses for acute symptoms and chronic symptoms differ.

o The physical examination should focus on signs of

dehydration, evaluation of skin turgor and mucous membranes, and

observation for hypotension or orthostatic changes. Abdominal and

neurologic examinations should also be performed.

o The presence of abdominal pain usually suggests an organic

cause; the location, severity, and timing of pain may indicate a

specific etiology.

o Warning signs such as chest pain, severe abdominal pain,

central nervous system symptoms, and fever; a history of

immunosuppression, hypotension, or severe dehydration; or older age

should prompt immediate evaluation.

o There are no diagnostic tests specific to determining the

etiologies of nausea and vomiting; tests should be directed based on

history and physical examination.

o A pregnancy test should be performed in any woman of

childbearing age and is needed before radiography.

o Proximal mucosal lesions and obstructions may be detected

by esophagogastroduodenoscopy or upper gastrointestinal radiography;

computed tomography may soon be the method of choice for detecting

intestinal obstructions.

o If no diagnosis is determined after initial evaluation,

gastric motility studies (eg, gastric emptying scintigraphy, cutaneous

electrogastrography, and antroduodenal manometry) may be considered.

* The third step, if no etiology can be determined, is to use

empiric therapy and treat symptoms.

o Medications that may be beneficial include phenothiazines

(eg, prochlorperazine), prokinetic agents (eg, metoclopramide), and

serotonin antagonists (eg, ondansetron).

o Trials determining the specific effectiveness of medication

for nausea and vomiting are limited; therefore, a trial of any

medication may be reasonable on an individual basis.

Pearls for Practice

* Nausea and vomiting are usually caused by the following:

iatrogenic, toxic, and infectious causes; gastrointestinal disorders;

and central nervous system or psychiatric conditions.

* The American Gastroenterological Association suggests a 3-step

approach to the initial evaluation of nausea and vomiting: recognizing

and correcting any consequences of the symptoms, trying to identify the

underlying cause and providing specific therapies, and using empiric

therapy and treating symptoms.

--

ne Holden, MS, RD < fivestar@... >

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