ER/PR-Positive Cancer? How an Antidepressants Helps Stop Hot Flashes and Night Sweats Without HRT
Photo by S.R. Stevens _ Jamaica
Venlafaxine (Effexor) vs. Pristiq (Desvenlafaxine) for Hot Flashes and Night Sweats
If you’re dealing with menopause-related hot flashes and night sweats, you may know that Red Clover and Black Cohosh are a great natural cures for many of us. However if you are, or have battled ER/PR-positive brest or ovarian cancers like I have, you know you can’t do hormone therapy. I was feeling hopeless and out of options till I learned that certain antidepressants can help. Two popular options are venlafaxine (Effexor) and Pristiq (desvenlafaxine). Both belong to the same family of medications called SNRIs (serotonin-norepinephrine reuptake inhibitors). Here’s a clear, simple comparison to help you understand how they stack up so you can make your own informed choices.
How Do They Work for Hot Flashes?
Both medications calm your brain’s thermostat (the hypothalamus), which becomes overly sensitive during menopause due to dropping estrogen levels. By boosting serotonin and norepinephrine, they help:
• Widen your body’s “comfort temperature zone”
• Reduce the frequency and intensity of sudden heat waves, flushing, and sweating
They work in very similar ways because Pristiq is the active form of venlafaxine — your liver actually converts venlafaxine into desvenlafaxine.
Effectiveness: Which One Reduces Hot Flashes More?
• Venlafaxine: Reduces hot flashes by 37–61% (most studies show around 48–55% at the typical 75 mg dose). It has the most research, including large trials in breast cancer survivors.
• Pristiq: Reduces hot flashes by 55–69% (often around 62–65% at 100 mg). It works quickly — sometimes within the first week.
Bottom line: They’re very close in effectiveness — both typically cut hot flashes and night sweats by about half. Venlafaxine simply has more studies behind it.
Key Differences
Dosing:
• Venlafaxine: Starts low at 37.5 mg once daily, then increases to 75 mg (sometimes 150 mg). Easy to adjust.
• Pristiq: Usually 100 mg once daily (50 mg is sometimes tried, but 100 mg is standard). Less flexibility in low dosing.
How Your Body Handles Them:
• Venlafaxine: Levels can vary more between people (depends on your genetics and liver function). More potential drug interactions.
• Pristiq: More predictable blood levels, cleared by the kidneys, fewer interactions. May be better if you have liver issues or take tamoxifen.
Side Effects: Very similar for both:
• Nausea, dry mouth, headache, dizziness, constipation, trouble sleeping
• Most improve after 1–2 weeks
Pristiq may cause slightly less nausea for some people, but the difference is small.
Cost:
• Venlafaxine: Generic and usually much cheaper
• Pristiq: Newer brand name (generics available) → often more expensive
Which One Is Better?
There’s no clear winner — they’re very similar. Doctors often try venlafaxine first because:
• More research
• Lower cost
• Flexible starting dose
Pristiq is a good alternative if venlafaxine causes too many side effects or if you need steadier medication levels.
Important Notes
Both are used off-label for hot flashes (not officially FDA-approved for menopause symptoms). They don’t fix estrogen levels — they just help your brain’s temperature control work better.
Always talk to your doctor before starting either one. They’ll consider your health history, other medications (especially tamoxifen), cost, and personal preferences. Never stop suddenly — both can cause withdrawal symptoms like dizziness or “brain zaps” if tapered too quickly.
This is general information only — not medical advice.
If you don’t have insurance, be sure to go to drugs.com for your discount card.
