SubQ injection needle size — seeking guidance

RENjutsu

RENjutsu

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Hey everyone, I've been on retatrutide for several weeks now and noticed effects (mostly fat loss) (though it's tough to tell if that was mostly due to the effort I put in). I recently ordered from a source on here. Before, I was using 13mm needles, and now I have 12.7mm ones (the type UK pharmacies provide). Are these too big or too long? I'm aware many folks go with 8mm — is it fine to not push the needle all the way in? What angle works best? I've got a fair bit of belly fat, so I figure an angled approach with the 12.7mm should do the job — just looking for any tips! Thanks
 
The insulin syringes I use measure 12.7mm with a 29 gauge needle. They're so small that you hardly notice them at all.
 
rettta said:

The insulin syringes I use measure 12.7mm with a 29 gauge needle. They're so small that you hardly notice them at all.
Click to expand...
My main concern isn't pain from the needle — it's making sure I'm doing the injection properly and not going into muscle, etc. From what I understand, with sizes like 4-8mm you can just inject straight in without worrying about angles and that sort of thing.
 
If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
 
WLBLD said:

If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
Click to expand...
The size I brought up isn't really an issue for me. What matters more is whether, based on experience, that size works reliably — getting the angle right, making sure the injection actually reaches SubQ, and I'm worried about inserting too far, etc.
 
When I'm buying, I grab whichever costs less: 32g or 31g in either 6mm or 4mm. I use them with pens and syringes alike.
 
RENjutsu said:

WLBLD said:

If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
Click to expand...
The size I brought up isn't really an issue for me. What matters more is whether, based on experience, that size works reliably — getting the angle right, making sure the injection actually reaches SubQ, and I'm worried about inserting too far, etc.
Click to expand...
As long as you pinch the skin, it isn't too long. I believe that's the needle length on my prescription Humira pre-filled syringe for subQ use.
 
nitetrak said:

When I'm buying, I grab whichever costs less: 32g or 31g in either 6mm or 4mm. I use them with pens and syringes alike.
Click to expand...
Pens typically come with 4mm or 6mm as the usual options.

Which means, naturally, I go with 5mm...😛
 
RENjutsu said:

WLBLD said:

If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
Click to expand...
The size I brought up isn't really an issue for me. What matters more is whether, based on experience, that size works reliably — getting the angle right, making sure the injection actually reaches SubQ, and I'm worried about inserting too far, etc.
Click to expand...
If the current depth isn't excessive, switching to a shorter needle later is an option as you continue losing and carry less tissue. Perhaps aim for a shallower insertion when a shorter size isn't available.
 
6mm, occasionally 8mm. With those, angles aren't necessary — just pinch and inject. After using 6mm I occasionally see a drip from the site; haven't had that with 8mm, though my experience is limited. I keep concentrations high enough that I'm typically injecting 15 units or fewer, but once I exceed 20 units I switch to the 8mm.

(These guidelines are based on whimsy.)
 
With sufficient belly fat, a 12.7 mm needle is not overly long, though proper technique matters. When doing subcutaneous injections:

Insert at a 45° angle while pinching the skin so you remain in the fat layer

Do not insert the needle only partway,

Needles in the 6–8 mm range tend to be simpler and less uncomfortable, yet the one you have can still be used without issue.
 
RENjutsu said:

Hey everyone, I've been on retatrutide for several weeks now and noticed effects (mostly fat loss) (though it's tough to tell if that was mostly due to the effort I put in). I recently ordered from a source on here. Before, I was using 13mm needles, and now I have 12.7mm ones (the type UK pharmacies provide). Are these too big or too long? I'm aware many folks go with 8mm — is it fine to not push the needle all the way in? What angle works best? I've got a fair bit of belly fat, so I figure an angled approach with the 12.7mm should do the job — just looking for any tips! Thanks
Click to expand...
I also go with 29/30 gauge needles at 12.7mm. Most of the time I pick the longer option, since it makes it simpler to draw the final remnants from a 3ml vial. That said, I pinch the skin, use a 45 degree angle, and only push in roughly 1/2 - 2/3 of the needle, so the injection stays in the Sub-q layer.
 
WLBLD said:

If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
Click to expand...
I realize this drifts a little from the main subject, but pen needles are fantastic! After a month of using pens, I went back to a 29ga insulin needle today to pull the remaining bit from a vial. That needle actually bounced right off my skin! I had to jab a 2nd time, harder, before it would go in.

Maybe it's because piercing the rubber stopper dulls it, plus the bigger gauge, but wow!
 
deluge said:

WLBLD said:

If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
Click to expand...
I realize this drifts a little from the main subject, but pen needles are fantastic! After a month of using pens, I went back to a 29ga insulin needle today to pull the remaining bit from a vial. That needle actually bounced right off my skin! I had to jab a 2nd time, harder, before it would go in.

Maybe it's because piercing the rubber stopper dulls it, plus the bigger gauge, but wow!
Click to expand...
With my prescription pre-filled syringes, this is a thing that occasionally occurs for me too. For over 20 years, I've been doing them every other week. Occasionally I'll pick a spot, it refuses to go in, so I shift about an inch away and then it works fine. As for my 31-32ga syringes for GLP-1, I've never run into a problem.
 
Right now I'm on 31g pen tips that are 5mm long. Pens are absolutely my favorite!! Before this I was on 8mm syringes, but those required a real hard jab because the needles got dull once I'd drawn my peps out of the vials. Another thing I like about the pen tips is that there's less waste. These days the syringes only get used for re-con and for filling up my pen vials
 
deluge said:

WLBLD said:

If your goal is the smallest possible option, pen needles are the tiniest. For something small and thin, 4mm 32g fits that description
Click to expand...
I realize this drifts a little from the main subject, but pen needles are fantastic! After a month of using pens, I went back to a 29ga insulin needle today to pull the remaining bit from a vial. That needle actually bounced right off my skin! I had to jab a 2nd time, harder, before it would go in.

Maybe it's because piercing the rubber stopper dulls it, plus the bigger gauge, but wow!
Click to expand...
I feel the same way — no interest in switching to something different. The fact that they're so tiny is a big plus for me.
 
RENjutsu said:

Hey everyone, I've been on retatrutide for several weeks now and noticed effects (mostly fat loss) (though it's tough to tell if that was mostly due to the effort I put in). I recently ordered from a source on here. Before, I was using 13mm needles, and now I have 12.7mm ones (the type UK pharmacies provide). Are these too big or too long? I'm aware many folks go with 8mm — is it fine to not push the needle all the way in? What angle works best? I've got a fair bit of belly fat, so I figure an angled approach with the 12.7mm should do the job — just looking for any tips! Thanks
Click to expand...
12.7mm does the job well. Grab a fold of skin, pinch about an inch, then push the needle straight in.
 
When using 32G or 31G needles, drawing the solution into the syringe can become more difficult.

For peptides that aren't spicy, I prefer not to go beyond 8 mm when injecting subcutaneously. Others opt for longer needles to achieve "deep subq" when dealing with spicy peptides.

My go-to choices are 6-mm syringes and 6-mm pen needles, though I haven't yet assembled my own pens.
 
RENjutsu said:

rettta said:

The insulin syringes I use measure 12.7mm with a 29 gauge needle. They're so small that you hardly notice them at all.
Click to expand...
My main concern isn't pain from the needle — it's making sure I'm doing the injection properly and not going into muscle, etc. From what I understand, with sizes like 4-8mm you can just inject straight in without worrying about angles and that sort of thing.
Click to expand...
Squeezing the skin together ought to reduce the concern about injecting into muscle
 
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