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Topic summary

Time to steady state after a dose increase

This is a generated summary. It shows the 9 most-liked posts from a topic of 164, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.
LC
l.cabreraTL2 Moderator1 Nov 2024#1

On the subject in the title: Time to steady state after a dose increase Working notes rather than a conclusion.

A documentation question rather than an analytical one.

I have a certificate in front of me that reports a purity figure, names a technique, gives a wavelength, and stops. No gradient, no column, no injection volume, no chromatogram.

What can I legitimately conclude from that document? My instinct is "almost nothing, but not literally nothing", and I would like to know where the people who read these professionally draw the line.

35 likes 21mo
HA
h.amankwahTL2 Moderator2 Nov 2024#14

This follows post #11 rather than contradicting it.

Bioavailability: oral semaglutide has low bioavailability (roughly 1%) due to peptide instability. That is why the oral dose (14 mg) is so much larger than the injectable dose. Comparing them by mass is meaningless.

32 likes 21mo
GR
g.rasmussenTL2 Moderator2 Nov 2024#19
Buchholz, post #10: Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive. Go to post

Worth separating two things that post #15 runs together.

Half-life: semaglutide ≈ 165–184 hours (about a week). Tirzepatide ≈ 5 days. Liraglutide ≈ 13 hours. The half-life determines how much accumulation happens at steady state and how long it takes to clear after stopping.

31 likes in reply to #10 21mo
D
DKwiatkowskiTL3Regular3 Nov 2024#26

Worth separating two things that post #22 runs together.

Albumin binding: semaglutide binds albumin through a fatty side chain, which sequesters the free form and extends the half-life. Tirzepatide also has albumin binding (different mechanism) which extends its half-life compared to an unmodified peptide.

30 likes 21mo
TS
taper_shiftTL3Regular4 Nov 2024#59
e.mensa, post #48: Worth separating two things that post #44 runs together. Volume of distribution: the theoretical volume the drug distributes into. For albumin-binding compounds, volume is reduced compared to drugs that do not bind protein. That is relevant to understanding how much free drug is available. Go to post

On post #55 — agreed on the reasoning, with one qualification.

Half-life: semaglutide ≈ 165–184 hours (about a week). Tirzepatide ≈ 5 days. Liraglutide ≈ 13 hours. The half-life determines how much accumulation happens at steady state and how long it takes to clear after stopping.

33 likes in reply to #48 21mo
EM
endpoint_marginTL2Member5 Nov 2024#91

Half-life: semaglutide ≈ 165–184 hours (about a week). Tirzepatide ≈ 5 days. Liraglutide ≈ 13 hours. The half-life determines how much accumulation happens at steady state and how long it takes to clear after stopping.

31 likes 21mo
CF
c.falkTL2 Moderator5 Nov 2024 · edited#118

I read post #116 twice before replying, because I had assumed the opposite.

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

30 likes 21mo
PK
p.krastevTL2 Moderator6 Nov 2024 · edited#136
s.oyelaran, post #96: 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. Go to post

Coming back to post #134, because the follow-up matters more than the original answer.

Renal clearance: these compounds are cleared partly via the kidney. In severe renal impairment, clearance is slowed and accumulation risk is higher. Dose adjustments might be needed.

33 likes in reply to #96 21mo
NS
no.silvaTL2 Moderator6 Nov 2024 · edited#162

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

31 likes 21mo

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