Topic summary

Filter needles: when they help and what they cost you

Devices › Syringes & needles needle gauge & length subcutaneous injection dead volume

This is a generated summary. It shows the 7 most-liked posts from a topic of 51, 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.

r.mwangiTL213 Dec 2025#4

Needle length for subcutaneous delivery is a question about tissue depth and injection angle together. Short needles at ninety degrees and longer ones at an angle reach comparable depths.

For what it is worth, the same held on the two occasions I checked.

22 likes 7mo

a.wikstromTL21 Jan 2026#16

Fixed versus detachable needles: insulin syringes usually have fixed needles (no dead volume loss to the hub). Luer-lock syringes use detachable needles (more dead volume). Fixed needles are preferred for small doses.

Reporting the observation and leaving the explanation open deliberately.

27 likes 7mo

b.friskTL29 Jan 2026#22

Where the filter needles reasoning breaks down for me is the step from the group result to the individual case. That step is almost never argued for.

31 likes 7mo

n.duarteTL214 Jan 2026#26

Saving this. It is the version I will quote when the question comes round again.

23 likes 6mo

z.nakamuraTL226 Jan 2026#36

TL4_Halvorsen, post #11: Following, with nothing to contribute beyond having asked the same thing elsewhere. Go to post

Adding the measurement that post #33 says would settle it.

Coring the stopper is a real phenomenon with repeated entries at the same point and blunt needles. Varying the entry point slightly and using a fresh needle prevents it.

Filing this under things that are true until someone shows me otherwise.

28 likes in reply to #11 6mo

a.almeidaTL231 Jan 2026#40

c.correia, post #39: Sharps disposal: needles and syringes should be disposed in a sharps container (a rigid, puncture-resistant container). Do not put them in regular trash. Many pharmacies accept filled sharps containers. Two people can read the same figure differently here and both be reasonable. Go to post

Adding a data point of agreement rather than a data point.

21 likes in reply to #39 6mo

outline_firstTL3Wiki editor4 Feb 2026#44

On filter needles, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one.

26 likes 6mo

Read the full topic (51 posts)

This topic was referenced in

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Reading a syringe in poor light, and how to avoid needing toDevices › Syringes & needles · 2 replies
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