Randomised trial, 2009
Does a hormone called allopregnanolone calm the body's startle reaction in PMDD?
No. Giving this hormone by injection made women feel more sedated but did not change their physical startle response, in either women with PMDD or healthy women.
What they did
A small double-blind, randomized study tested 16 women with PMDD and 12 healthy women. Each woman received an intravenous injection of allopregnanolone and, 48 hours apart, a placebo injection, during the luteal phase. Startle response (a muscle reflex to sudden noise) and how well it was filtered out (prepulse inhibition) were measured with electrodes.
What they found
The injection raised allopregnanolone blood levels to 50-70 nmol/l, similar to levels in pregnancy. Women with PMDD had significantly lower allopregnanolone levels than healthy women (p<0.05). Both groups felt more sedated after the hormone injection than placebo (p<0.01), but the injection did not change the startle response or its filtering, and there was no difference between the PMDD and healthy groups.
What it means for you
A single dose of this hormone made women feel drowsy but did not reduce the measured startle reflex, so this particular calming effect was not confirmed. The study was small and looked at a lab measurement, not everyday mood symptoms.
16 / 12
Women with PMDD / healthy controls
50-70 nmol/l
Allopregnanolone blood level reached
p<0.01
Sedation increase (both groups)
About the study
- Original title
- Allopregnanolone has no effect on startle response and prepulse inhibition of startle response in patients with premenstrual dysphoric disorder or healthy controls
- Authors
- Kask K, Bäckström T, Lundgren P et al.
- Journal
- Pharmacology, biochemistry, and behavior
- Year
- 2009
- Study design
- Randomised trial
- What was tested
- Single intravenous injection of allopregnanolone compared with placebo.
- Read the paper
- doi.org/10.1016/j.pbb.2009.02.014
Topics
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