Can venlafaxine (Selective Serotonin-Norepinephrine Reuptake Inhibitor) be used to treat vasomotor symptoms?

Venlafaxine for Vasomotor Symptoms

Venlafaxine is recommended as an effective medication for the treatment of vasomotor symptoms, with a typical dose of 75 mg daily providing optimal benefit while minimizing side effects. 1

Efficacy and Dosing

• Venlafaxine (a Serotonin-Norepinephrine Reuptake Inhibitor) significantly reduces hot flash frequency and severity, with studies showing a 61% reduction in hot flash scores at the 75 mg daily dose compared to 27% with placebo 1
• The optimal dose appears to be 75 mg daily, which balances efficacy with tolerability; lower doses (37.5 mg) show modest improvement (37% reduction) while higher doses (150 mg) don't provide additional benefit 1, 2
• Long-term treatment (8 weeks) with low-dose venlafaxine (37.5 mg/day) has demonstrated continued improvement in vasomotor symptoms with a 53% reduction in hot flash frequency and 59% reduction in hot flash score 2

Comparison with Other Treatments

• Venlafaxine has been shown to be more effective than clonidine in reducing the frequency and severity of hot flashes in breast cancer patients 1
• In a randomized crossover study comparing venlafaxine with gabapentin, both treatments resulted in similar reductions in hot flash severity, but 68% of participants preferred venlafaxine 1
• The clinical efficacy of venlafaxine and other antidepressants appears modest compared to estrogen therapy, though direct head-to-head studies are lacking 1, 3

Side Effects and Considerations

• Common side effects include dry mouth, decreased appetite, nausea, and constipation, which are typically dose-related 1
• Approximately 10-20% of individuals withdraw from treatment due to adverse events, but this is less likely with lower doses 1
• Unlike some SSRIs (particularly paroxetine), venlafaxine has a lower risk of interfering with tamoxifen metabolism, making it a safer option for breast cancer survivors on tamoxifen therapy 4
• Venlafaxine should be tapered gradually when discontinuing to prevent withdrawal symptoms 1

Special Populations

• Venlafaxine is particularly useful for breast cancer survivors with vasomotor symptoms, including those on tamoxifen therapy 2
• The American Society of Clinical Oncology specifically recommends venlafaxine as an option for managing vasomotor symptoms in cancer survivors 1

Alternative Options

• Other pharmacologic options for vasomotor symptoms include:
  • Other SNRIs like desvenlafaxine 5, 6
  • SSRIs such as paroxetine (though caution with tamoxifen), citalopram, and escitalopram 4, 3, 7
  • Gabapentin, medroxyprogesterone acetate, and cyproterone acetate 1
• Non-pharmacologic approaches that may be beneficial include:
  • Acupuncture, which has been shown to be equivalent to or better than drug treatments in some studies 1
  • Cognitive behavioral therapy 1
  • Slow-breathing techniques and hypnosis 1

Clinical Algorithm for Venlafaxine Use in Vasomotor Symptoms

1. Start with venlafaxine 37.5 mg daily for 1 week to minimize initial side effects
2. Increase to 75 mg daily if tolerated and needed for symptom control
3. Evaluate response after 4 weeks; significant improvement should be seen by this time
4. Continue effective treatment as needed, with periodic reassessment
5. When discontinuing, taper gradually to prevent withdrawal symptoms