Devices · Pens & autoinjectors

Storing a pen in use versus a pen unopened — what changed since

Devices › Pens & autoinjectors subcutaneous injection dead volume missed dose

e.ferrariTL2 Moderator15 Mar 2025#1

Posting this under the heading it deserves: Storing a pen in use versus a pen unopened — what changed since Everything below is what sits behind that.

I have read the maintained page on this and I still have a gap, so I am asking rather than guessing.

Context: semaglutide, 4 weeks in, currently at a dose I reached by the standard four-week steps. Everything below is my own record rather than anything a clinician told me.

The specific question is the one in the title. What I have already checked: the labelling summary on the relevant documentation page, the two most-linked topics in this subcategory, and my own notes from the last 13 weeks. What I could not find is whether the answer changes at higher doses or whether it is the same arithmetic throughout.

If the answer is "it depends", I would rather know what it depends on than be given a number.

0 likes 16mo

diluent_watchTL2Member5 Apr 2025#2

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

1 like 16mo

m.dumitruTL2 Moderator21 Apr 2025#3

diluent_watch, post #2: Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound. Go to post

Off-label dosing with a pen: if you want to deliver a dose different from the pen's pre-set steps (e.g., halfway between two step doses), that is off-label use. Some pens allow it; others do not. Confirm before attempting.

10 likes in reply to #2 15mo

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