What are the recommended treatments for managing hot flashes?

Management of Hot Flashes

For moderate to severe hot flashes, start with either venlafaxine 37.5 mg daily (increasing to 75 mg after 1 week) or gabapentin 900 mg/day at bedtime as first-line therapy, with the choice depending on concurrent symptoms and medication interactions. 1, 2

First-Line Nonhormonal Pharmacologic Options

SSRIs/SNRIs are highly effective first-line agents:

• Venlafaxine reduces hot flash scores by 37-61% and is preferred by 68% of patients over gabapentin despite similar efficacy 2
• Start at 37.5 mg daily and increase to 75 mg after 1 week if symptoms persist 1
• Paroxetine 7.5-20 mg daily reduces hot flash frequency, severity, and nighttime awakenings by 62-65% 2
• Critical warning: Avoid paroxetine and fluoxetine in women taking tamoxifen due to CYP2D6 inhibition 1, 2
• SSRIs/SNRIs are contraindicated with monoamine oxidase inhibitors and should be avoided in bipolar disorder due to mania risk 1, 2

Gabapentin is equally effective and may be preferred in specific situations:

• Gabapentin 900 mg/day reduces hot flash severity by 46% compared to 15% with placebo 2, 3
• Choose gabapentin when: the patient is on tamoxifen, has multiple medications (no drug interactions), or has concurrent sleep disturbance from hot flashes 2
• Take at bedtime to maximize benefit for sleep-related symptoms 2
• Side effects affect up to 20% of patients but improve after the first week and largely resolve by week 4 2

Treatment Algorithm and Timing

Review efficacy at specific intervals:

• For SSRIs/SNRIs: assess at 2-4 weeks 1, 2
• For gabapentin: assess at 4-6 weeks 1, 2
• If no response within these timeframes, the treatment is unlikely to be effective and should be switched 1

If first-line therapy fails:

• Switch between venlafaxine and paroxetine if one SSRI/SNRI is ineffective 1
• Switch to gabapentin if SSRIs/SNRIs are not tolerated or ineffective 1
• Consider clonidine 0.1 mg/day (oral or transdermal) for mild to moderate symptoms, which reduces hot flashes by up to 46% but has higher discontinuation rates (40%) due to dry mouth and drowsiness 1

Nonpharmacologic Approaches

Evidence-based behavioral interventions:

• Paced respiration training (20 minutes daily) shows significant benefit in reducing hot flashes 1, 2
• Structured relaxation techniques with adequate training are effective, but simply advising patients to "relax" without guidance is not helpful 1
• Weight loss ≥10% of body weight may eliminate hot flash symptoms 2, 3
• Smoking cessation improves frequency and severity 3

Acupuncture has mixed but promising evidence:

• Some studies show equivalence or superiority to venlafaxine or gabapentin 2, 3
• Safe if sterile needles are used 1
• Avoid the affected arm in breast cancer survivors with prior axillary surgery 1

Limited efficacy options for mild symptoms:

• Vitamin E 800 IU/day has limited efficacy but is reasonable for patients requesting "natural" treatment 1, 2
• Warning: doses >400 IU/day are linked to increased all-cause mortality 1

Hormonal Therapy Considerations

Menopausal hormone therapy (MHT) remains most effective:

• Reduces hot flashes by approximately 75% compared to placebo and by 80-90% overall 2, 4, 5
• Use transdermal estrogen formulations due to lower rates of venous thromboembolism and stroke 2
• Use at the lowest effective dose for the shortest duration possible 2

Absolute contraindications to estrogen:

• History of hormone-related cancers 2
• Abnormal vaginal bleeding 2
• Active or recent thromboembolic events 2
• Active liver disease 2
• Pregnancy 2

Special Population: Breast Cancer Survivors

Avoid estrogen and tibolone due to recurrence risk 1

Preferred agents in order:

• Venlafaxine or gabapentin as first-line 1
• Paroxetine only if not on tamoxifen 1
• For advanced breast cancer or severe symptoms affecting quality of life, estrogen may be considered after fully informed discussion, with the decision ultimately resting with the patient 1

Common Pitfalls to Avoid

• Do not combine gabapentin with SSRIs/SNRIs—there is no additional benefit 1
• Do not use black cohosh due to reports of liver failure 1
• Require gradual taper when discontinuing SSRIs/SNRIs to minimize withdrawal symptoms 2
• Do not expect benefit from exercise, relaxation without structure, or primrose oil—these lack proven efficacy 6