Rapamycin dose determination

At the risk of beating a dead horse, discussion in another thread made me realize how little I know about the correct dose. So, two specific questions:

  1. What parameters do you use to determine you are taking enough Rapa?
  2. What parameters do you use to determine you are taking too much?
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actuallyā€¦ how little all of us know about the ā€œcorrectā€ dose.

Based on the information presented in this thread: The Key issue of Dosing Levels and Intervals for Best Rapamycin Outcomes

I have decided that I donā€™t think Iā€™ll truly ā€œknowā€ if Iā€™m taking enough rapamycin ever (or at least for the next decade or moreā€¦

Given that - that ā€œhigher generally tends to result in bettter longevity resultsā€ in all the animal studies (except one, where they maxed out in female mice and the longevity gains plateaued at 128ppm, if I recall correctly)ā€¦

My belief is that the best we can do is test different dosing levels and timing approaches on our own bodies, track blood test and functional results closely - and modulate in a way that we think will optimize results.

I think daily dosing in mice is roughly equivalent to about once every 4 days or so in human terms given the speed that mice metabolize rapamycin is about 4 times faster.

Sirolimus
Dose
Mouse
mg/kg/day
Dose
Mouse:
Blood/Sirolimus
Level
Human
mg/kg/day
Dose
Dose for 60kg Human Daily Dose adjusted for longer half-life (/4)
4.7ppm āˆ¼2.24 3 to 4 ng/mL 0.182 mg/kg 10.92 mg 2.73 mg
14ppm ~6.67 9-16 ng/mL 0.542 mg/kg 32.54 mg 8.135 mg
42ppm ~20 23-80 ng/mL 1.626 mg/kg 97.56 mg 24.39 mg
126ppm ~60 4.878 mg/kg 292.68 mg 73.17 mg
378ppm ~180 45 to 1800 ng/mL 14.634 mg/kg 878.04 mg 218 mg
Sirolimus
Dose
mg/kg/day
Dose
Blood/Sirolimus
Level
Male Median LS Increase Female Median LS Increase
4.7ppm āˆ¼2.24 3 to 4 ng/mL 3% 16%
14ppm ~6.67 9-16 ng/mL 13% 21%
42ppm ~20 23-80 ng/mL 23% 26%

Based on the FDA animal to human dosing conversion guide here.

Note: Ā½ life for sirolimus in mice is approx. 15 hours, vs. approx. 62 hours in humans. So, mice metabolize sirolimus approximately 4 times faster than humans.

My approach has been increasingly to optimize around avoiding the ā€œtoo muchā€ issue, and doing this by tracking and mitigating all the possible negative side effects, which for me seem to be around lipid increases. Iā€™m in the phase of testing and monitoring different rapamycin doses, and lipid management approaches, from diet to medications and supplements - testing them all. Iā€™m early in this process, so nothing to report yet.

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The problem with increasing dose, if my math is right, is that if you double your dose, you add a full half life to clearance time which is another 62 hrs.
Of course we donā€™t even know how much clearance is needed.

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Yes - so as part of this new plan Iā€™ll also try adopting the blood/sirolimus level testing that was suggested by @McAlister in his post: Rapamycin Cycling (Time Off) - Who Is Right? - #4 by McAlister

I like the three test approach to blood / sirolimus levels. With the Mareck testing at $59, the triple test approach is not too expensive:

So, when you get results, do you have peak levels that are too high, too low? Do you have trough levels that are too high?

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I would love to do the same, but Sirolimus blood tests are unavailable in my location. :frowning:

However I am very interested in everyoneā€™s results

@RapAdmin what is your current Rapa dosing schedule?

Check with hospital labs (especially transplant clinics) they do this test routinely. I was also thinking it is not available but phoned the transplant clinic and they have it and it is quite inexpensive out of pocket too.

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Thanks. I will check it out.

Nothing ventured. Nothing gained.

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