Gabapentin's effects on hot flashes in postmenopausal women: A randomized controlled trial

OBJECTIVE: To evaluate whether treatment with the anticonvulsant gabapentin may be effective in reducing hot flash frequency and severity. METHODS: A randomized, double-blind, placebo-controlled trial was conducted in 59 postmenopausal women with seven or more hot flashes per day examining the effects of gabapentin 900 mg per day on hot flash frequency after 12 weeks of treatment. Subsequently, study patients were enrolled in a 5-week, open-label treatment phase, during which patients could increase the dose of gabapentin to 2700 mg per day, if needed. RESULTS: After 12 weeks of double-blind treatment, intention-to-treat analysis showed that gabapentin 900 mg per day was associated with a 45% reduction in hot flash frequency and a 54% reduction in hot flash composite score (frequency and severity combined into one score) from baseline, compared with 29% (P = .02) and 31% (P = .01) reductions, respectively, for placebo. Four patients (13%) in the gabapentin group and one (3%) in the placebo group withdrew from the double-blind study because of adverse events. Fifteen patients (50.0%) in the gabapentin group reported at least one adverse event, compared with eight patients (27.6%) in the placebo group. Higher, open-label gabapentin dosing was associated with 54% and 67% reductions in hot flash frequency and composite score from baseline, respectively. CONCLUSION: Gabapentin is effective in reducing hot flash frequency and severity in postmenopausal women.