This gets cited here weekly, usually second-hand, so it is worth setting out what it does and does not establish.
The distinction that matters is unopened versus in use. Unopened vials are stable refrigerated for their labelled shelf life and tolerate a limited excursion to room temperature. Once reconstituted, the clock is much shorter and is set by the preservative rather than by the peptide — bacteriostatic water's benzyl alcohol is what buys you multiple draws over weeks. Sterile water has no preservative and turns a multi-dose vial into a single-use one.
Where I think it is weakest: the follow-up is short relative to how long people actually take these drugs, so durability is an assumption here rather than a finding.
So the question, as narrowly as I can put it: what a temperature excursion actually does, and what distinguishes an unopened vial from one already in use. Tell me what I have not thought of.
CarlaRPh_TPA said:The distinction that matters is unopened versus in use.
Agreed, though "tolerable" needs defining. A dose you tolerate by eating almost nothing is not tolerated, it is being paid for somewhere else — usually in lean mass, sometimes in adherence three months later.
CarlaRPh_TPA said:The distinction that matters is unopened versus in use.
I read this differently from CarlaRPh_TPA, on substance rather than tone. Freezing is the one to avoid, and freeze-thaw more so. Ice-crystal formation and the concentration changes at the phase boundary drive aggregation, and aggregated peptide does not recover on thawing. A vial that has been frozen and thawed is not rescued by returning it to the fridge.
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Browse GL BiochemAnswering the narrow version, because the broad one does not have a single answer. Albumin binding above 99% is the whole reason weekly dosing works, and it is also why the trough matters more than the peak. People who dose late are not losing a peak, they are letting the trough fall, and the appetite effect tracks the trough.
pete_manc_UK said:Agreed, though "tolerable" needs defining.
All true, with one condition: that curve is for people who reached the dose on schedule. Anyone who slowed the ladder for tolerability is on a different, flatter curve, and comparing yourself with the published mean will make you feel like a non-responder when you are not.