One concrete data point for the thread. Practical: unopened, refrigerated at 2 to 8°C; in use, refrigerated and used within the preservative-limited window; never frozen; and a visual check every time — a haze that does not settle is a reason to stop, not to wonder.
Following on from MASHdoc_SA — and this may be the naive question:
How much material I am losing to dead space, and whether that explains why a 10mg vial gives me nine usable draws rather than ten?
Dr.PeteFamMed said:Practical: unopened, refrigerated at 2 to 8°C; in use, refrigerated and used within the preservative-limited window; never frozen; and a visual check…
Coming at Dr.PeteFamMed’s question from a different direction. 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.
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Follow-up: it was dead space. Switching to a low-dead-space fixed-needle syringe gave me the tenth dose back.
TinaHashiRN said:The distinction that matters is unopened versus in use.
No disagreement with TinaHashiRN. One condition attached. The arithmetic is right and one caveat matters: a U-40 syringe changes the markings, not the volumes. If someone hands you U-40 and you read it as U-100 you will be 2.5 times out, and that error has a direction — it is always an overdose.