Shorter needles :(

I wanted to bring this up because of my experience trying the short needles with a pen recently.

A couple of weeks ago, there was a discussion on short pen needles (4mm) versus longer pen needles. I think the recommendations for shorter needles are very much “safety” based. I never thought the shorter needles worked as well, but I believe that because they remove the risk of “inadvertent” intramuscular injection (IM), they are the recommendation now. (their quote - “Absorption rates differ greatly depending on how active the muscle is (insulin is absorbed more rapidly in very active muscles), making muscle injection more unpredictable, potentially leading to dangerous lows.” :scream: )

And also because of things like “patient compliance” - the shorter ones are “less scary”, so people are more likely to take their insulin when they are supposed to.

But I wanted to give them a fair shake, so I went back to them and tried them again…

Here is what I saw:
The worst BG’s I can remember. I didn’t recognize the disease. I could see things like they were posts on another site - people talking about how their BG spikes after eating, how their insulin doesn’t seem to work, how long it takes their insulin to come in, what am I doing wrong, etc, etc…

It was incredibly eye-opening. I really seemed like I had a different disease. I had to stop. I was so happy to go back to the 8mm needles.

For small injections they did not seem to make much difference. For example, a 1/2 unit injection was no big deal, I didn’t notice a difference.

But when I did larger amounts, like for meals, I spiked like crazy.

It’s possible I am getting a bit of IM with the 8mm needles. But whatever the reason, I will never go back to those 4mm’s.

I have used both enough - in all kinds of real-life scenarios, not the confines of a lab. I have used them for different amounts, different meals, running, sitting, correcting small highs, correcting big highs, breakfast, lunch, dinner, snacks. Those are things that don’t happen in a lab. In one of the experiments I saw referenced, they actually only did a total of 56 injections with 28 people. That’s ridiculous.

I want to go to every T1 who has ever complained about post-meal spikes, give them a hug, and give them a box of 8mm’s and say, “Try these.”


I think you are onto something! I feel like the insulin kicks in sooner on the pump than when I did MDIs with 4 or 5 mm syringe tips (not much body fat and the 6 mms sometimes really hurt).


Eric, what exactly is your injecting M.O. with 8mm needles? With my son, 8MM would go straight into muscle almost anywhere he injects.

I am assuming you are folding the skin before you inject? Any chance you could show a couple of picks of an injection in a lean part of the body?

I don’t pinch or fold, except on abdomen. I just inject. That’s why I am probably getting some IM on occasion.

If I inject in my butt without a pinch, that is not going into muscle. Thighs maybe partial. Arms maybe partial. Calves definitely (that’s my go-to spot when I want to do IM).

Sometimes I pick a spot to get IM on purpose, but not always.

I guess. Pick the spot (except you don’t get pictures of my butt, so you can quit asking…). :joy:h


Well, rats. I was really hoping. OK – how about the thigh or the arm?

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Heh. I’d need a 16mm (maybe 30mm) needle to do an IM in my abdomen.


I had a good laugh :slight_smile: Me too!


That is really interesting, I’ve never heard that mentioned before. Now I’m really curious to try them if I can find them.


Just search for “8 mm insulin needles”

when I tried the omni - pod, total daily insulin dosage was ridiculously small. the lowest setting was too much at times for me. I had to repeatedly suspend the pod. It had to have something to do with the needle length.

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Very useful thread.


eric taught me this trick: 8mm needle filled with appropriate amount of insulin into any muscular area.( i am skinny everywhere, so its hard for me to miss a muscle) last night i used my thigh. i stretched out my skin so that there was no subq hiding anywhere, and i jabbed that needle into my thigh muscle like i was spearing an animal.

i went from 350 down to 106 within the hour. now even if i have just changed my pump site, i do not ever get such a rapid response.


I’ve always used 8 mm needles since I started using pens 20 years ago, and I’ve always liked them. Recently the pharmacist was trying to convince me to switch to 4 mm ones, and I refused but she gave me a sample to try. So I tried them, and I hated them. I found they actually hurt more than the 8 mm ones. Now I’m using 12 mm needles for some injections and like them as well. Though I notice that every box of 8 mm needles I get also now comes iwth a sample of 4 mm needles.

Weirdly, with the metal infusion sets I use for my pump, I hate the 8 mm sets and much prefer the 6 mm ones. I find the 8 mm ones are prone to hurting and getting more irritated and 6 mm is much more comfortable. So I do think that perhaps 8 mm needles are capable of hitting muscle. Not a bad thing for shots (in my opinion), but really annoying for pump sites.


Did you hate them because they hurt more, or did you notice a difference in delivery?

I think the shorter ones take forever for the insulin to come in. I noticed a big difference in time with 4mm versus 8mm.

I didn’t notice any difference in delivery. My blood sugar is so variable that it’s hard to tell sometimes what causes what. So there could have been a difference that I just didn’t notice. (I also didn’t use them for very long—only a few shots.)

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Doctors everywhere may be doing disservice by recommending 4mm needles!


I prefer 8mm for everything bolus, except for the occasional 12mm. I’m using my remaining 6mm for basal only.


Is it possible that:

Some of us may be having difficulties with better BG management because we are being handicapped by the shorter needles (prescribed and recommended to us) which take FOREVER, as opposed to the 8mm or longer which may be helping the insulin go into muscles and therefore become effective earlier?

I feel really stupid not having read or reread this thread more carefully. But better late than never. Longer needle, insulin gets to work faster , also out of system faster. It’s not quite Afreeza. Anything has to be an improvement over 30 minutes or more of pre-bolusing!!

For bolusing if we were to use 8mm or longer needles, are we effectively TRYING to get the insulin into the muscles, and not the fat?


This thread may be better called: "the untold ‘dangers’ of shorter needles - what they don’t tell you. LOL.


Except for basal, children, why would we wish to use short needles, ever?

Is there an advantage to have insulin start slow (requiring pre bolus)?

It would seem to me that: start to work quickly and be out of our system quickly would be ‘safer’. If we have fatty/carby food that result in a delayed BG rise, inject again. The insulin can get in, get out quickly.