Paroxetine
Paroxetine is an SSRI used off-label for menopausal hot flashes and FDA-approved at the lower 7.5 mg Brisdelle dose specifically for vasomotor symptoms.
How it works
Paroxetine is the only SSRI with an FDA-approved indication for menopausal hot flashes, at the lower 7.5 mg Brisdelle dose. At standard antidepressant doses (10–40 mg), it is sometimes prescribed off-label for hot flashes when concurrent depression or anxiety is also being treated. The mechanism is serotonin reuptake inhibition in hypothalamic thermoregulatory centers. Trial data shows roughly 40–60% reduction in hot flash frequency. Onset is typically within one to two weeks.
A critical interaction: paroxetine is a potent CYP2D6 inhibitor. It substantially reduces the metabolism of tamoxifen into its active form endoxifen, potentially undermining tamoxifen's effectiveness in breast cancer prevention or treatment. Women on tamoxifen should discuss this interaction with their oncologist before starting paroxetine — alternative non-hormonal options with less CYP2D6 inhibition are generally preferred in that context.
How to track Paroxetine
- Hot flash frequency per day before and after starting — the primary signal of therapeutic response.
- Hot flash severity alongside frequency — trials used both measures, and severity captures quality-of-life impact that count alone misses.
- Nausea and dry mouth — most common early side effects; usually dose-dependent and often transient.
- Libido and sexual function — SSRIs at any dose can affect sexual response; worth tracking separately.
- Any concurrent tamoxifen use — the CYP2D6 interaction is clinically significant and should be flagged in your record.
- Log hot flash frequency for at least one week before starting to create a genuine baseline — without it, you cannot assess whether the treatment is working.
- If you are taking standard antidepressant doses rather than 7.5 mg Brisdelle, note the dose in your log — the evidence base differs across dose levels.
- Rate nausea separately from hot flash severity during the first two weeks; these are different phenomena and your physician needs to distinguish them.
- If you are also on tamoxifen, log that you discussed the interaction with your oncologist and the date — this is a patient safety record worth maintaining.
- Track libido as a separate item — it is easy to attribute changes to menopause rather than the medication, and a log helps distinguish the two.
Questions to ask your physician
- My hot flash frequency before starting was [X] per day. At [N] weeks on paroxetine [dose], my current daily average is [Y]. Is that response at the expected level?
- My severity log shows hot flashes are [less/equally] intense despite frequency change — does severity data change how we evaluate the response?
- I've been logging libido changes since [date] — is that consistent with this medication at my dose, and does it suggest a change?
- I want to stop paroxetine. Can we review my log and set a taper schedule rather than stopping abruptly?