Abstract

Hot flashes are a complication of androgen deprivation therapy for prostate cancer. A phase III study showed that use of low-dose gabapentin was well tolerated and moderately decreased the frequency of hot flashes due to androgen deprivation therapy when taken for 4 weeks. The current study, an open-label continuation of the randomized study, examined the efficacy and toxicity of gabapentin when taken for (an additional) 8 weeks. Patients were allowed to start, or continue, gabapentin and to titrate the dose to maximum efficacy, up to 900 mg/d. They were asked to complete a hot flash diary daily and keep weekly logs of toxicity, satisfaction with hot flash control, and quality of life. The moderate reduction in hot flash frequency and severity in the randomized phase of the study appeared to be maintained during this continuation phase. Men originally receiving the placebo or lowest dose of gabapentin (300 mg/d) had improved hot flash control relative to that at the end of the randomized phase. Minimal adverse effects were reported. These findings suggest that low-dose gabapentin is moderately efficacious for at least 12 weeks of hot flash treatment in men undergoing androgen deprivation therapy for prostate cancer and seems to be well tolerated. (NCT00028572)