Cohort study, 2012
How quickly does fluoxetine start working for PMDD symptoms?
Very quickly. Fluoxetine improved irritability, sadness, anxiety, and mood swings within hours, with clear daily improvement by the second day.
What they did
12 women with PMDD took fluoxetine 20 mg daily during the luteal phase (the second half of the menstrual cycle). Another 12 women with PMDD received no treatment. Both groups rated their symptoms every hour before and after treatment, and also completed daily symptom questionnaires.
What they found
Hourly ratings showed significant improvement in irritability, sadness, anxiety, and mood swings after starting fluoxetine. Daily symptom scores improved significantly by the second day of taking the medication. The speed and pattern of improvement matched how symptoms naturally improve when menstruation starts.
What it means for you
Fluoxetine can work very fast for PMDD emotional symptoms, within days rather than weeks. This is much faster than how antidepressants usually work for depression. The study was small with only 12 women taking medication, so the results may not apply to everyone.
12
women receiving fluoxetine
20 mg
daily dose
second day
when symptom improvement was clear
About the study
- Original title
- Rapid response to fluoxetine in women with premenstrual dysphoric disorder
- Authors
- Steinberg EM, Cardoso GM, Martinez PE et al.
- Journal
- Depression and anxiety
- Year
- 2012
- Study design
- Cohort study
- What was tested
- Fluoxetine 20 mg daily during the luteal phase
- Open access
- Yes
- Read the paper
- doi.org/10.1002/da.21959
Topics
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