Does anybody have experience with this dosage ? I asked the author for more details but not yet replied
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Compounded rapamycin can have lower bioavailablity if it’s not in nanocrystals or similar to improve solubility. So it might not be 36 mg in the first place. If they could measure their serum sirolimus levels that would answer the question of much they really absorb from the products from that compounding pharmacy.
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To clarify, unless a compound pharmacy uses enteric capsules or some other means to enable the rapamycin to survive stomach acid, you will get negligible to zero serum levels. Stomach acid destroys rapamycin.
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I used to say all the time previously that it required enteric coating for improved bioavailablity but I’ve changed my mind.
For example rapamune is not enteric coated, instead the tablets are film coated. It’s suspended in e.g nanocrystals to improve solubility, which suggest stomach acid is not the issue. But if someone has info to the contrary I would be happy to know about it.
From the other topic the author of 36 mg said:
Rapamune is also available as a solution (in Switzerland whwre I am). I take 14 mg and measured blood levels of 66 ng/l after 2 hours (avg of few measurements) with subsequent sharp declines. So i suppose stomach acid is no issue.
Regardless of the mechanism by which branded rapamycin achieves greater bioavailability, we know from the PEARL trial that compounded rapamycin is only about a third as bioavailable. So the 36mg compounded dose translates to about 12mg bioavailability. It’s as if they took 12mg branded rapamycin. However that’s just the start, because rapamycin is metabolized at different rates depending on the individual. Some people metabolize extremely quickly and so need greater or more frequent dosing to achieve physiological impact. Furthermore, this in turn is impacted by what agents rapammycin is taken concurrently with - drugs, supplements, food, fasted etc. The bottom line is that to really know how much rapamycin exposure you are getting, there is no other way than multiple blood tests for sirolimus levels spread out in time to assess peak, half life etc.
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I doubt the accuracy of that doctor to be honest because I’ve only seen reports of compounding pharmacies not being bioavailable. It might be a new thing or an exception however.
Gree, I did a whole serie of multiple measurements at 46, 60, 112, 150 hrs. The Half time for me was 42 hrs, which is lower than standard - plausible as I am 4A3 rapid metabolizer. It’s important to start measurements after 40 hrs, or you get erroneous results.
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