Subcutaneous absorption kinetics and site differences — setting out what I have, and where I think it stops being reliable.
A follow-up question about Subcutaneous absorption kinetics and site that I did not know to ask the first time.
The earlier thread answered what I asked. What I should have asked is below, and I think it is the one that matters.
SNAC (the oral bioavailability enhancer): sodium N-(8-[2-hydroxybenzoyl]amino) caprylate transiently raises gastric pH and promotes absorption. Without it, oral bioavailability is too low for clinical use. With it, bioavailability is still variable between people.
Coming back to the opening post, because the follow-up matters more than the original answer.
Bioavailability for subcutaneous administration in this class is high but not complete, and the published figures are formulation-specific.
Post #3 is right about the mechanism and I think understates the practical bit.
The time to maximum concentration after a subcutaneous dose in this class is measured in days rather than hours, which surprises people expecting an injection to act quickly.
I have changed my mind on this once already, so take it as current rather than settled.
Fasting requirement for oral semaglutide: food and large fluid volumes reduce absorption. The fasting window (30 minutes before and 30 minutes after) is designed to maximise absorption. Violating it measurably reduces exposure.
The honest answer is that it depends, and here is what it depends on.
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Coming back to: Washout: how long is long enough, and for what purpose
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Time to steady state after a dose increase
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+57 | 61 | 708 | 1d |
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Half-life, steady state, and accumulation worked through — a second dataset
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+110 | 126 | 14k | 4mo |
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Titles that describe the question, not the situation
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+137 | 153 | 22k | 8mo |
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Designing a personal experiment that could change your mind — one year on
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An ABAB design with a data table and honest limitations
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2 | 45k | 5mo | |
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Second pass at: Choosing a concentration on purpose rather than by accident
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+44 | 48 | 1k | 19mo |
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Follow-up: Semaglutide versus liraglutide head to head: reading STEP 8 carefully
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+1 | 5 | 11k | 20mo |