Lab study, 2001
Does withdrawal of a progesterone metabolite increase seizure risk around menstruation?
In rats, withdrawal of allopregnanolone (a progesterone metabolite) increased how easily seizures happen, supporting the theory that this withdrawal contributes to increased seizures during menstruation in women with epilepsy.
What they did
Researchers created a model of high progesterone levels in female rats, then used a drug (finasteride) to block the conversion of progesterone into allopregnanolone. They then tested the rats' sensitivity to seizures.
What they found
Allopregnanolone levels dropped by 86% after finasteride treatment. After withdrawal, rats were more likely to have seizures when challenged with a seizure-triggering drug. The seizure threshold decreased by 30-35% compared to control rats. The 50% seizure dose was 46 mg/kg in withdrawing animals compared with 73 mg/kg in non-withdrawn animals and 60 mg/kg in normal rats.
What it means for you
Withdrawal of allopregnanolone during the menstrual cycle may explain why some women with epilepsy experience more seizures around menstruation. The limitation is that this is an animal model, not a human study.
86
percent reduction in allopregnanolone after finasteride treatment
30-35
percent reduction in seizure threshold
46
mg/kg seizure dose in neurosteroid-withdrawing animals
About the study
- Original title
- Neurosteroid withdrawal model of perimenstrual catamenial epilepsy
- Authors
- Reddy DS, Kim HY, Rogawski MA
- Journal
- Epilepsia
- Year
- 2001
- Study design
- Lab study
- What was tested
- Finasteride (a drug that blocks conversion of progesterone to allopregnanolone)
- Open access
- Yes
- Read the paper
- doi.org/10.1046/j.1528-1157.2001.10100.x
Topics
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