Gabapentin (Neurontin), Estrogen, and Placebo for Treating Hot Flushes: A Random

[Guest guest]

Obstet Gynecol. 2006 Jul;108(1):41-48.

Gabapentin, Estrogen, and Placebo for Treating Hot Flushes: A

Randomized Controlled Trial.

Reddy SY, Warner H, Guttuso T Jr, Messing S, Digrazio W, Thornburg L,

Guzick DS.

Department of Obstetrics and Gynecology, University of Rochester

School of Medicine and Dentistry, Rochester, New York; Department of

Obstetrics and Gynecology, University of Indiana School of Medicine,

Indianapolis, Indiana; and Department of Neurology, University of

Buffalo School of Medicine, Buffalo, New York.

OBJECTIVE: To compare the efficacy of gabapentin, estrogen, and

placebo in the treatment of hot flushes.

METHODS: We performed a randomized, double-blind, placebo-controlled

trial of 60 postmenopausal women to assess the efficacy of estrogen

and gabapentin in the treatment of moderate-to-severe hot flushes.

Participants were randomly assigned to receive either 0.625 mg/d of

conjugated estrogens (n = 20), placebo (n = 20), or gabapentin

titrated to 2,400 mg/d (n = 20) for 12 weeks. Participants recorded

frequency and severity of baseline hot flushes on a hot flush diary

for 2 weeks before randomization and for 12 weeks after

randomization. The primary outcome measure was the weekly hot flush

composite score, which takes into account both severity and frequency

of hot flushes. Secondary outcome measures were differences in pre-

and posttreatment scores pertaining to depression (Zung Depression

Scale) and other climacteric symptoms (Greene Climacteric Scale).

RESULTS: Intention-to-treat analysis showed that the reduction in the

hot flush composite score for both estrogen (72%, P = .016) and

gabapentin (71%, P = .004) was greater than the reduction associated

with placebo (54%) at the conclusion of the 12th week. The extent of

reduction in hot flush composite score, however, was not

significantly different between estrogen and gabapentin (P = .63). No

differences were seen between groups in the Zung Depression Scale, or

in any of the Greene Climacteric subscales except for the Somatic

Symptom cluster, which was significantly greater in the gabapentin

arm than in the placebo arm. Despite a lack of group differences in

adverse events, the Headache, Dizziness, and Disorientation cluster

appeared with greater frequency in the gabapentin group. Estimation

of the number needed to harm in this cluster suggests that these

symptoms may occur with every fourth patient treated with gabapentin.

CONCLUSION: Despite the small scale of this study, gabapentin appears

to be as effective as estrogen in the treatment of postmenopausal hot

flushes.

CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT 00276081. LEVEL

OF EVIDENCE: I.