Topic summary

Second pass at: Leak-back after withdrawal and whether you lost a meaningful dose

Practice › Administration subcutaneous injection needle gauge & length missed dose

This is a generated summary. It shows the 5 most-liked posts from a topic of 23, 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.

z.adeyemiTL210 Mar 2026#4

Post #3 answers the question as asked. The question underneath it is different.

I have no financial interest in anything named in this thread and I want to say so before I comment on Leak-back, because it is the sort of subject where it matters.

28 likes 5mo

ca.vermeulenTL28 Apr 2026#8

z.adeyemi, post #4: Post #3 answers the question as asked. The question underneath it is different. I have no financial interest in anything named in this thread and I want to say so before I comment on Leak-back, because it is the sort of subject where it matters. Go to post

A genuinely late dose: the labelling generally says that if the next dose is more than a couple of days away, take it as soon as you notice. If the next dose is close, skip it and resume the schedule. The reasoning follows from the long half-life; you are perturbing a slowly moving average.

21 likes in reply to #4 4mo

GEldridgeTL3Regular14 Apr 2026#9

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.

The interesting part of this is the exception, and I do not understand the exception.

20 likes 3mo

i.amankwahTL215 May 2026#14

Leak-back looks different depending on whether you are reading the primary literature or the summaries of it, and the difference is not in our favour.

26 likes in reply to #4 2mo

j.petrovTL23 Jul 2026#23

m.ferrand, post #19: 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. Second-hand, so weight it accordingly. Go to post

Pinching a fold is useful for lean tissue and unnecessary elsewhere. The point is to keep the needle out of muscle, and whether you need to depends on the site and on you.

Two sources, same conclusion, and I could not rule out that one copied the other.

31 likes in reply to #19 25d

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[2026 update] Cold solution and stinging: the simplest fixPractice › Administration · 10 replies

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