@koalou If the needles are using the international standard (Birmingham gauge), then they should be the same.

There is a different French system, but it's only for catheters, not needles.

@SleepyCatten
I had the Birmingham gauge page open but it seems I didn’t compare the correct lines  (shouldn’t have done that while in a work meeting xD)

Still, it seems like a substantial difference between the 25G 25 mm you are using and the 20G 40 mm that this seller is recommending for IM with a oily product Oo

@koalou Some places recommend much thicker needle gauges than required, or base their recommendations on vials with much-thicker carrier oils.

Homebrew vials tend to use MCT oil for a number of reasons, but a major one is that it's less viscous than carrier oils that are commonly used in commercial vials (e.g., sesame, sunflower, castor oil etc.).

With a less-viscous oil, you don't need thicker needles, so you can easily use something like a 22G (black) needle for drawing up and a 25G (orange) needle for injecting.

In fact, some folks swear by thinner 27G (grey) or even thinner needles, typically up to around 30G (yellow), with some going as thin as 32G (deep green)!

The suggested needle lengths depend on what it's going to be used for.

For a drawing up needle, 25 mm, 31/32mm, and 38 mm are typically fine.

For intramuscular injection, the shortest recommended is usually 25 mm and the longest is broadly 38 mm. 25 mm is fine for most legs (including rather chonky ones like ours).

For subcutaneous (subQ), the longest recommended is 16 mm, with 13 mm being the shortest commonly available without moving to fixed needles. With fixed needles, it's possible to get 30G or even 32G 8 mm needles!

For thick, intramuscular injections on commercial products, particularly where it's one injection per vial or package, the needles are often much thicker.

For example, Nebido recommends an 18G drawing up needle, and a 20G to 22G injection needle (for intramuscular).

As another example, triptorelin (Decapeptyl) commonly uses a 20G needle for mixing the powder into the suspension liquid, and another 20G for injection.

For any vial where you will be drawing up liquid multiple times, the goal is to use the thinnest needle needed, as this reduces the risk of "coring" the vial (i.e., making a hole too large for the stopper to seal, which can let contaminants into the vial liquid).

Hope this makes sense. Our mind isn't exactly firing on all cylinders today.

@SleepyCatten
I would definitely recommend not going much thinner than 25g for IM injections that involve a carrier oil. 18-23 is generally the recommended range, but 25-27g is definitely fine when the solution is less viscous. The general "rule" is to use the thinnest needle the medication will reasonably push through.

Considerations should include risk of clogging while in the muscle tissue, and bending/distortion in cases of involuntary contractions of the muscle. Considering how fragile 29g and smaller can be, it's definitely something to think about. Especially given that IM injections are typically done with longer lengths than what you'd use for subcutaneous or IV shots. I second the recommendation for 25mm needles. For many people it's less intimidating. The main thing is you want to ensure it actually goes into the muscle. Most folks don't need much longer than 38mm to reach the muscle, but some do.

Since the oil is there to create a depot that is absorbed over time, less viscous carrier oils tend to be the ones to be processed faster (meaning you'll end up needing to inject more frequently) and the oils that are processed more slowly tend to be more viscous as well. This isn't any sort of judgement, just an FYI. The most viscous thing I've had to inject is one of my past immunosuppressants. Almost as thick as honey that was.

@koalou

@h3mmy @SleepyCatten
Alright, better look silly now than later when I discover I forgot something or bought something inappropriate.

(Don’t worry too much if you something wrong, I won’t actually order before tomorrow, probably after lunch at the earliest)

So, here’s my current list of things to order:
- hand sanitizer – my understanding is that it’s better to use soap then that to get rid of everything?
- sterile nonwoven compresses – come in pairs in the same packaging; to use with 70% alcohol, one to clean the vial before inserting the needle to draw, the other to clean the skin before injection
- 1 mL syringes
- 25G 25mm needles – both drawing and injecting

What do you think?

For the needles, I could also go for 26G or 30 (both at 12mm) for drawing to reduce hole size but it’ll take longer to draw, won’t it? (Should have payed better attention to what we used when I went to the injection "workshop", it took some time to draw the 0.1mL)

Also, do you recommend changing needle between drawing and injection even if the gauge doesn’t change? (As I understand it, it would be better)

@koalou
Soap and water is your friend and is the preferred approach to cleaning your hands

Compresses are fine. I personally use 91% IPA, but then I also just use paper towel for the application of my shots (eg immunosuppressants) Some folks prefer cotton balls, and some folks absolutely despise the squeaky little things.

Yes, you want to clean the vial and then separately clean the injection site with the alcohol.

At first I was like 1mL syringes are pricier, especially with a luer lock. But then you said you only have a 0.1mL draw, for which a 1mL makes a practical difference compared to a 3mL, and you probably have that right.

0.1mL sounds really small to me, but I don't know the specifics of your regimen. Almost every transfem I know does 0.5mL shots at different concentrations, and a couple do 0.3 or 0.6 (again depending on concentration and ester).

25g at 25mm sound okay. I don't know your carrier oil so I'm assuming it's fine for that diameter. If in doubt 23g is what works for cottonseed oil based on folks I've helped with shots.

Yes, use a separate needle to draw vs inject. The stab dulls the needle, and would make it more painful.

No, don't stress about needing a thinner needle for the draw. Assuming you have a vial that has an elastomeric seal that meets pharmaceutical standards, it can withstand a lot more stabs than people think. I can send you a write up with more details. But in short, you should technically be able to make holes once around the inner ring and once around the outer ring (to avoid stabbing the same area multiple times) before it is considered "worn out" or the seal ineffective. So you should be fine using the same needle gauge as you are for injecting. If it's drawing too slow, then it's also probably not the right gauge for injecting for you.

https://lgbtqia.space/@h3mmy/114132969617459619

Data about self-sealing stopper durability: https://pubmed.ncbi.nlm.nih.gov/23636157/

@SleepyCatten

@koalou Seconding all of Kat’s information on needle length and gauges, and the sanitising info!

Even if I’m injecting 1ml or less, I personally prefer the 3ml syringe which is shorter and wider than the 1ml syringe usually. For me, the 3ml are much easier to handle because I’m typically holding the syringe in one hand, and a tiny bat patient in my other hand. Depending on your injection site and dexterity, this might not be an issue for you though. ☺️ @h3mmy @SleepyCatten