Progesterone acts on progesterone receptors throughout the body, including the central nervous system, breast tissue, uterus, and cardiovascular system. Two effects matter most for the indications biio. uses it for.
The first is direct progesterone receptor activity, which counterbalances the effects of unopposed oestrogen — relevant for cyclical symptoms, perimenopausal patterns, and combined hormone therapy.
The second is the effect of allopregnanolone, a progesterone metabolite produced when progesterone is taken orally or as a troche. Allopregnanolone is a positive modulator of the GABA-A receptor, which is why oral progesterone has a calming, sleep-supporting effect that transdermal progesterone does not have to the same extent. The sedating effect at the biio. dose is intentional when used for sleep; it is also the reason oral dosing is at night and not in the morning.
In MCAS patients with a clear pattern of oestrogen-driven flares, micronised progesterone can sometimes reduce the cyclical worsening — although the evidence here is clinical rather than trial-based, and the response is individual.
PROGESTERONE RECEPTOR ACTIVITY
Acts on progesterone receptors throughout the body, counterbalancing the effects of unopposed oestrogen.
ALLOPREGNANOLONE & GABA-A
Oral or troche use produces allopregnanolone, a positive modulator of the GABA-A receptor, giving a calming, sleep-supporting effect.
ROUTE-DEPENDENT EFFECTS
Oral and troche routes leverage the sedating metabolites that support sleep, while transdermal use minimises systemic sedation for daytime indications.
CYCLICAL FLARE SUPPORT
In MCAS patients with oestrogen-driven flares, it can sometimes reduce cyclical worsening, though the response is individual.