Randomised trial, 2023
Do very low doses of fluoxetine help emotional PMS symptoms?
Yes. Low doses of fluoxetine (5 to 10 mg daily) reduced emotional PMS symptoms when taken only before menstruation, with 10 mg being more effective.
What they did
40 women with emotional PMS (average age 29.7 years) were studied over two menstrual cycles. In cycle 1, they took no medication. In cycle 2, they took fluoxetine (2, 5, or 10 mg daily) for about 7 days before their period. PMS symptoms were measured using the DRSP scale.
What they found
Cycle 1 confirmed emotional PMS with increased symptoms before menstruation. In cycle 2, the 5 mg dose reduced symptoms by 33.5% and the 10 mg dose by 48.4%. The 10 mg dose was most effective, with 70% of participants having symptom reductions greater than 40%.
What it means for you
Ultra-low-dose fluoxetine taken only before the period may help emotional PMS, with the 10 mg dose appearing most helpful. This is a small pilot study, so larger studies are needed to confirm these findings and determine the best dose.
40
women studied
33.5%
symptom reduction at 5 mg dose
48.4%
symptom reduction at 10 mg dose
About the study
- Original title
- Low doses of fluoxetine for the treatment of emotional premenstrual syndrome: a randomized double-blind, placebo-controlled, pilot study
- Authors
- Maranho MCMF, Guapo VG, de Rezende MG et al.
- Journal
- Psychoneuroendocrinology
- Year
- 2023
- Study design
- Randomised trial
- Participants
- 40
- What was tested
- Low-dose fluoxetine (2, 5, or 10 mg daily) taken for about 7 days before menstruation
- Read the paper
- doi.org/10.1016/j.psyneuen.2023.106360
Topics
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