What published stability data actually covers, and what it does not — what changed since

What published stability data actually covers, and what it does not — what changed since — that is the question, and I have not found it answered plainly anywhere I have looked.

Practical question with the units stated, because I have seen how quickly these go wrong without them.

I have a 5 mg vial of semaglutide and I am working to a 0.5 mg step. My syringes are U-100 insulin syringes, 1.0 mL barrel.

I can do the arithmetic and I have done it twice, getting the same answer both times, but I would like someone to check the reasoning rather than the number — specifically whether I have thought about the residual volume correctly, and whether the graduation I am landing on is one a person can actually read.

Vial integrity: once a vial is entered with a needle repeatedly, the rubber closure degrades and the integrity fails. Using the same vial repeatedly over weeks or months carries increasing risk of contamination. Single-use vials entered once are lowest risk.

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.