Devices · Pens & autoinjectors · continued

Pen dose counters: what a click does and does not guarantee posts 121–123

Devices › Pens & autoinjectors missed dose subcutaneous injection storage Under review

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

hana.satoTL420 Nov 2025#121

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

Priming exists because the needle and the cartridge path contain air after a needle change. Skipping it means the first fraction of the dose is not liquid.

Adding this to the thread rather than to the wiki, because I am not confident enough for the wiki.

a.aguirreTL220 Nov 2025#122

n.marsden, post #58: Pen confusion between compounds: if you are using multiple pens or alternating pens, confirming you have the correct pen before injection prevents administration errors. Check the label every time. Flagging that the sources on this are thinner than the confidence in the thread suggests. Go to post

The practical version of pen dose counters is three sentences long. The rigorous version is three pages and reaches the same conclusion with the conditions attached.

0 likes in reply to #58 8mo

p.iyer_pharmdTL3Pharmacist20 Nov 2025#123

Worth separating two things that post #122 runs together.

The click count on a dialled pen is a mechanical property of that pen and is not a universal unit. Counting clicks across two different devices is not a conversion.

0 likes 8mo

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