BACKGROUND AND PURPOSE:

• Shan et al. (AJOG, 2019) assessed the efficacy and safety of gabapentin (trade name Neurontin) and pregabalin (Lyrica) for the treatment of vasomotor symptoms

METHODS:

• Systematic review and meta-analysis
• Data sources
  • Multiple databases | WHO clinical trials registry
• Inclusion criteria
  • RCTs and randomized crossover studies
  • Studies that compared gabapentin and pregabalin among women with menopausal vasomotor symptoms to other treatment modalities including supplements
• Study design
  • Two independent reviewers assessed bias and extracted data
  • Random-effects models were used for analysis
• Primary outcomes
  • Reduction in frequency of vasomotor symptoms from baseline | Severity | Duration

RESULTS:

• 19 RCTs and 2 randomized crossover trials | Total of 3519 participants
  • 6 studies included breast cancer survivors who were on tamoxifen or aromatase inhibitors 
• Compared to placebo, gabapentin reduced hot flash frequency (low to moderate evidence)
  • After 4 weeks: Mean difference –1.62 (95% CI, –1.98 to –1.26)
  • After 12 weeks: Mean difference –2.77 (95% CI –4.29 to –1.24)
• Composite score
  • After 4 weeks: standardized mean difference –0.47 (95% CI –0.71 to –0.23)
  • After 12 weeks: standardized mean difference –0.77 (95% CI –1.15 to –0.40)
  • Benefit was seen in both postmenopausal participants and patients with breast cancer
• Daily gabapentin dosage
  • Range: 300 mg to 2400 mg
  • Subgroup analysis: 900 mg dose did not results in outcomes substantially different from analysis of all ranges of dosages
• Adverse events
  • Gabapentin group experienced higher risk of
    • Dizziness: Risk ratio (RR) 4.45 (95% CI, 2.50 to 7.94)
    • Somnolence: RR 3.29 (95% CI, 1.97 to 5.48)
• Compared to other therapies
  • Estrogen was more effective at reducing hot flash frequency than gabapentin
  • No difference seen between gabapentin and antidepressants
  • Data too limited to provide risk analysis for other treatments
• Pregabalin was only assessed in 2 trials
  • Pregabalin vs placebo |  Pregabalin superior in reducing hot flash frequency and severity scores
  • Pregabalin vs stellate ganglion block in patients with breast cancer | Better outcomes in ganglion block group

CONCLUSION:

• Gabapentin was found to be superior vs placebo for the relief of vasomotor symptoms, although less effective than estrogen
• Evidence for pregabalin “was limited yet promising”

Learn More – Primary Sources:

Efficacy and safety of gabapentin and pregabalin in patients with vasomotor symptoms: a systematic review and meta-analysis

Related ObG Topics:

North American Menopause Society: Hormone Therapy Statement

The WHI Randomized Trials: Is Menopausal Hormone Therapy Associated with Long-Term Mortality?

Is Gabapentin an Effective First Line Drug for Vulvodynia?

Can Mindfulness Alleviate Menopausal Hot Flashes?