Topic summary

Air bubbles in a subcutaneous injection: the honest risk assessment — does this still hold?

Practice › Administration injection site rotation missed dose aseptic technique subcutaneous injection Wiki

This is a generated summary. It shows the 5 most-liked posts from a topic of 31, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

baseline_tableTL2Member22 Feb 2026 · edited#2

Community wiki post. Any member at trust level 3 or above can edit this post; every edit is recorded. Last edited by NLoughran on 14 May 2026.

8 May 2026 — bench_notes: Corrected an arithmetic slip in the second example.
8 Mar 2026 — o.lindgren: Plain-language pass on the opening paragraph.
14 May 2026 — NLoughran: Restructured into sections so the outline is navigable.

Editors: bench_notes, o.lindgren, NLoughran

Coming back to the opening post, because the follow-up matters more than the original answer.

For anyone finding this later: the short answer on Air bubbles is that it depends on one thing, and the rest of the thread is people identifying which thing.

22 likes 5mo

cohort_watchTL2Member28 Feb 2026#6

sharps_bin, post #4: Two things can be true about Air bubbles at once: the mechanism is plausible and the evidence for the size of the effect is thin. Most of the argument here is people defending the first against attacks on the second. Go to post

I had written a reply contradicting post #4 and deleted it. Here is what survived.

Cold solution and stinging: warming the vial in your hands for a minute before injection reduces the stinging sensation substantially. This is the simplest thing to try if injections are uncomfortable.

30 likes in reply to #4 5mo

DSakamotoTL3Regular8 Mar 2026#12

c.falk, post #9: If you have to inject at a different time of day than usual, that is a much smaller perturbation than it feels for a weekly compound with a week-long half-life. One case, stated as one case. Go to post

The version of Air bubbles that circulates here is a simplification of a simplification. It is not wrong, but it has lost the conditions under which it holds, and those conditions are where the interesting cases live.

30 likes in reply to #9 5mo

d.magalhesTL2Member13 Mar 2026#16

baseline_table, post #14: A site rotation scheme that actually works: abdomen, outer thigh, back of arm, outer hip. Rotate through them in order, move a minimum 2 cm between consecutive sites, note the site with each dose. If a local reaction appears you have the history. If you rotate properly you will not get lipohypertrophy from overuse of one area. I would… Go to post

A new needle for each injection is not fussiness. A needle blunts on first use and a blunted needle is the reason the second injection hurts more than the first.

Where I would look next, rather than where I would stop.

22 likes in reply to #14 5mo

f.piresTL217 Mar 2026#19

Alcohol swabbing and letting the site dry is the whole of the preparation for a subcutaneous injection into intact skin. Injecting before it dries is what stings.

That is all I can say without guessing.

31 likes 4mo

Read the full topic (31 posts)

This topic was referenced in

Injecting into an area that has become firm: why not toPractice › Administration · 92 replies
Rotating between abdomen, thigh and upper arm: absorption differencesPractice › Administration · 2 replies

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