Hi Folks,
I am 70 years old, in good shape, 6’3" 188 pounds, 13% body fat. I took 5mg rapamycin with a glass of grapefruit juice. Exactly 2 hours later, drew blood. The results are below. Should I be concerned? Or should I skip the grapefruit juice? Or is this perfect? Thanks!
sirolimus 46.7 ng/ml
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Bicep
#2
5 is a common weekly dose. GFJ multiplies by 3 or 4, so maybe you should go every 2 or 3 weeks at that rate.
I use 3 or 4 with GFJ every 14 days. When I go higher my lipids and fasting glucose go too high. I don’t know if taking drugs to fix that is worth it since we don’t know for sure whether it even does anything for longevity. It helps my brain and my arthritis and I don’t hardly ever have even a cold. It’s been a couple years now since I had a sniffle.
I think your dose is too high, but if it works for you then use it. Nobody knows the truth.
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Herm
#3
If you checked your blood level 12-24 hours later, and again ~96 hours later, you would have at least two points on the terminal elimination part of the blood concentration curve and could get a rough idea of the half-life. Once you know that you could decide if you want to keep a minimum amount of rapamycin around, in which case you could dose every 3-4 half lives, or you could decide to wait until it is fully cleared for a period of time before another dose. But as @Bicep wisely points out “Nobody knows the truth.” For me, I got annoying aphthous ulcers with more frequent doses, so I’m dosing at a dose of 3 mg every three weeks. There is a lot of variability, and everyone has a different risk threshold. BTW do you plan on drinking GFJ once or twice a day ongoing, or is this just taken with rapamycin to increase absorption? In the former case, your half-life will be increased ~3.5x +/- so keep that in mind.
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Thanks Folks. It seems the GFJ experiment was a success. So, I’ll do the same test without GFJ and I’ll test again in 24 hrs & 72 hours.
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As you already know or you would probably not be trying to increase the bio-availability with GFJ, Rap has relatively low bio-availability.
Consuming with fat is also considered a bio-availability enhancer for this drug.
We do GFJ (night before) and EVOO (the morning of) along with our 6mg every 2 weeks.
Just for a little clarity on GFJ and how that affects the Rap dose. Fundamentally the total dose will not be above the value (mg consumed) of the indicated dose…
If you take 5mg of Rap, the max amount you can get from that is 5mg.
GFJ cannot increase the amount of Rap in a cap 
but can increase what is available to your system.
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I get your point here, but I am not sure I agree with your premise. To use an extreme example, if a person with very dark skin could make their skin react to the sun the way a person with very light skin would react to the sun, you wouldn’t be advising them well if you said “Well, the most sun you can get in thirty minutes is thirty minutes of sun.” The reality is that thirty minutes of sun (even at the same altitude, with the same cloud cover, on the same day of the year) is not going to have the same impact on people with two different levels skin pigmentation. Taking GFJ before rapa is like making your skin lighter before sun exposure. It could be a reasonable strategy, but I wouldn’t be quite so sanguine.
I think most folks on here agree that some mix of peak blood concentration and area under the curve will be the targets for optimizing dose.
Since everybody metabolizes the drug differently based on their characteristics, you would ideally choose a combination of rapamycin dose and grapefruit juice, fat, etc. that gets you to the target you have chosen (as measured by, e.g. peak blood concentration, or as suggested by @szalzala your 24-hour post dose blood concentration).
If you think about it, the less bioavailable the drug is in the first place (on average), the more you risk spiking your blood concentration over the optimal target by making adjustments that increase the bioavailability. It’s all about keeping the conditions consistent and testing blood concentration. That’s why the bottle, at least if you get it from a US pharmacy, literally says: Take with food or on an empty stomach, but do it the same way every time. That’s so that you can monitor your blood measures until you get to the right dose and then keep taking that dose and not having bioavailability changing based on your behavior and screwing up the blood concentration relative to your target.
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It’s a simple point, was not trying to make anything of it
I’ve seen peoples expectations exceed the basic understanding of what enhancing bio-availability can actually do.
You have a good handle on it. Measuring is the only way to know for sure what your system is doing with what you consume.
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Peak levels can be very tricky to catch. It occurs about 2 or 3 hours after ingestion, spikes pretty high, and then drops off quickly. Unless you’re drawing blood every 10 minutes or something, it would be very hard to catch the peak.
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