Gabapentin is an anticonvulsant that has been shown to be an effective nonhormonal option for reducing menopausal hot flashes, showing significant benefits for vasomotor symptoms and additional advantages for sleep.  Current guidelines list gabapentin as a recommended nonhormonal therapy for vasomotor symptoms in women who cannot or prefer not to use hormone therapy.

Efficacy of Gabapentin for Vasomotor Symptoms

Multiple randomized, placebo-controlled trials in naturally menopausal women and breast cancer survivors show that gabapentin reduces hot flash frequency and severity more than placebo. In most studies of postmenopausal women, gabapentin at 900 mg/day reduces hot flash frequency and/or severity by roughly 35–50% from baseline, with some higher-dose trials reporting reductions up to 60–80%.

In a trial of 420 breast cancer survivors, gabapentin 900 mg/day decreased hot flash frequency by approximately 41% at 4 weeks, compared with 17% with placebo; 300 mg/day was less effective. Other studies using doses from 900–2,400 mg/day in divided doses show improvements in hot flash scores comparable to estrogen therapy in some analyses, although higher doses were associated with greater side effect burden.

Gabapentin is generally well-tolerated. Side effects include drowsiness, sedation, dizziness, and impaired coordination.

Gabapentin is not an antidepressant and has limited direct effect on mood; however, reductions in vasomotor symptoms and improved sleep can indirectly improve overall quality of life and daytime functioning. 

Recommendations

The 2023 North American Menopause Society (NAMS) nonhormone therapy position statement classifies gabapentin as a recommended pharmacologic option for vasomotor symptoms with Level I evidence, NAMS notes that gabapentin provides mild to moderate improvements in vasomotor symptom frequency and severity and is particularly useful when symptoms are most bothersome at night.

As with most medications, it is recommended to start low and go slow, increasing the dose based on symptom control and tolerability.

• Initial dose: 100–300 mg at bedtime
  
• Titration: Increase by 100–300 mg/day every 3–7 days as needed.  
• Dosing Frequency: Nighttime-only dosing (for example, 300–900 mg at bedtime) is often used to promote sleep and to minimize daytime sedation. At higher doses, or if preferred, adding morning or midday doses to reach 300 mg three times daily (900 mg/day).
  
• Usual effective dose: 900 mg/day, which has the best evidence for vasomotor symptom reduction.
  
• Higher doses: Some trials used 2,400 mg/day with greater symptom reduction but a substantially higher burden of side effects (e.g. dizziness, somnolence).

Patients should also be counseled to avoid taking gabapentin together with alcohol or other central nervous system depressants (such as opioids or benzodiazepines), because concomitant use can enhance sedation and respiratory depression.