Pharmacology · Pharmacokinetics · continued

Peak-to-trough ratio at steady state for a weekly agent — the long version posts 61–62

Pharmacology › Pharmacokinetics semaglutide missed dose tirzepatide worked example Under review

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

KnowltonTL326 Jul 2026#61

Collapsed as off-topic by two members at trust level 3 or above

Coming back to post #57, because the follow-up matters more than the original answer.

Steady state is approached in roughly four to five half-lives. For a compound with a week-long half-life that is four to five weeks, which is where the escalation interval in the trials comes from.

It is worth checking rather than assuming, which costs nothing.

s.achebeTL227 Jul 2026#62

Post #60 is right about the mechanism and I think understates the practical bit.

The thing about Peak-to-trough ratio that took me longest to accept is that a plausible mechanism is not evidence of an effect. It is a reason to look, not a result.

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This topic was referenced in

Coming back to: Half-life, steady state, and accumulation worked throughPharmacology › Pharmacokinetics · 18 replies
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