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Syringe Selection 1/2" vs 5/16"

19 replies11 peopleApr 29, 2026☆ Follow
Summary

does shorter needle length reduce bruising for subcutaneous injections of peptides like reta and ghk

users report mixed experiences with 5/16 inch versus 1/2 inch insulin syringes. some find the shorter 30g or 31g needles cause less bruising on the abdomen while others prefer deeper penetration with longer needles or report no difference at all. switching injection sites to upper glutes helped one person avoid bruising with ghk. shorter needles are also discussed in relation to burning sensations during ghk injections.

What this discussion establishesWhere people disagree

whether shorter or longer needles cause less bruising and burning varies by individual and compound

Still open

optimal length and gauge for minimal discomfort across different peptides

Nothing here is advice.

19 replies · 11 people
KeenCinder27archiveopening postApr 29

I wanted to post my observation here. Maybe it helps somebody. My partner got some bruising from the earlier needle size during her injections. So I tried a different size instead. This size appears to produce reduced bruising around the abdominal region. In addition this size appears less expensive. I got the replacement ones in a bulk pack at a lower cost.

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PatientBeacon15archiveApr 29

Appreciate you posting this. I got the longer size by error instead of the shorter one and now find myself liking it better for whatever reason. It appears to result in reduced marks since the insertion goes deeper. Just as you do, I like the higher numbered sizes. Do you mind telling me the source of your bargain? Obtaining them is becoming more difficult in Florida because some outlets insist on a prescription and won't send particular models.

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PlainAlder11archiveApr 29

Don't recognize that label at all. The only ones I keep around are thirty one gauge eight millimeter in half and full milliliter sizes. Ever tried the thirty one gauge five sixteenths inch version? We think they're great.

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QuietMarble97archiveApr 29
↳ replying to @PlainAlder11

i like the easytouch quarter inch six mm 31g syringes. only found one shop selling the shorter tips.

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KeenCinder27archiveApr 30
↳ replying to @PlainAlder11

I haven't given the finer ones a shot yet. A bulk order of a thousand coarser needles is what I went with. That should last me an incredibly long while. By then some robotic AI assistant could be handling the injections before my supply runs low.

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BrightMeadow28archiveApr 30
↳ replying to @KeenCinder27 (opening post)

Slight bruising showed up after injecting GHK into my stomach area. I moved the shots to the top of my rear about an inch under the belt line and everything went smoothly after that. My belly works fine for Reta. A video online showed me the location.

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WarmPebble45archiveApr 30
↳ replying to @KeenCinder27 (opening post)

Right now my injections rely on thirty one gauge needles that come in at six millimeters. Shorter lengths would be my preference if they existed on the market. Standard pen needles for insulin measure four millimeters. Subcutaneous delivery works with lengths above two millimeters except in cases of uncommon skin problems.

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PlainAnchor67archiveApr 30

Tried out nearly all the sizes and thicknesses for insulin syringes. They all feel the same to me. Haven't run into any bruising whatsoever. Ended up picking the 30 gauge half inch version when injecting peps.

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PlainAlder11archiveApr 30
↳ replying to @QuietMarble97

i never saw those when i ordered mine. i have four hundred easy touch and bds right now so im good.

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LevelTimber64archiveApr 30

i like the six mm. they seem to work better with my glp than ghk-cu.

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SteadySignal83archiveMay 1

Thirty gauge works better for me than thirty one. Those skinnier ones flex way too much and I've managed to warp a couple while pulling liquid from the bottle.

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IronLantern24archiveMay 2

i been using a convi pen with both eight mm and four mm needles for my ghk-cu. when i use the four mm it burns no matter where i pin.

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SharpHarbour41archiveMay 2
↳ replying to @IronLantern24

so is the eight less burn than the four?

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LevelTimber64archiveMay 2
↳ replying to @SharpHarbour41

ive heard the short needles are more burn for ghk-cu. its been true for me.

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IronLantern24archiveMay 2
↳ replying to @SharpHarbour41

I think so. It could sink in further.

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IronLantern24archiveMay 2
↳ replying to @LevelTimber64

i think so. i have some five mm also but i havent tried those yet.

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BrightMeadow28archiveMay 2

Curiosity got the better of me lately. Over the past three days I've administered that compound straight into my stomach area. There was zero stinging or any marks or soreness at all unlike what happened earlier. The syringe I'm using is a short thin insulin type.

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LevelTimber64archiveMay 2
↳ replying to @IronLantern24

Normally I go for the eight millimeter size. I gave the six millimeter option a shot with that copper peptide. Even after mixing in plenty of bacteriostatic solution during reconstitution it went poorly enough that I skipped any repeats. I have not checked the balanced copper to basic ratio version either.

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PlainAlder11archiveMay 2

which ones? i should be good for about four years.

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PlainAlder11archiveMay 3

ill keep that in mind for the future. im not a member and we dont have one in the pt charlotte area.

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Syringe Selection 1/2" vs 5/16" · ZyraTrack Community