As many of you know, I've been playing with IntraMuscular injections for that past several months. As reported in other threads, everything's about 2x as fast as subcutaneous (I call them subQ) injections.

So far, I've only used them for corrections, and usually only significant ones.

Today I gave a meal bolus a try. I was nervous, worried it would get ahead of my digestion, and I'd have a low.

Well, that didn't happen. In fact, it was so incredible it was almost like having a fulling working pancreas, with no insulin resistance!

I ate a standard lunch I have every week. Well known. Very well. Usually, pre-bolus 40 minutes ahead, eat, and follow up with a modest extended bolus over 4 hours to cover protein and fat (my weekly In 'n Out Double Double :-))

I usually stay under 140, but dip down into the 70s, most of the time, before glucose hits the blood and things start rising. Typically, I'll get a 50-60 pt rise if I've done everything right, and 4 hours later I'm back down in the 80s/90s.

This time? First, no extended bolus. Just the initial pre-bolus, but injected IM. I waited 25 minutes instead of 40 before stuffing my maw.

All I can say is.... WOW!!!!!!! I flat-lined. I couldn't believe it. My BG never did more than wiggle a little bit. It dropped 10 from when I injected down to 68; then, rose all the way to the stratospheric 95, peaked, and is now back down to 82 5 hours later.

With less insulin (remember, no extended TAG bolus).

I may just dump the pump and go back to MDI with pens, using 12mm needles for IM injections more often than not. This is very exciting!!

Of course, there is greater risk. I'm guessing we'll discuss it :-) However, for the right, diligent people, I believe its a completely manageable risk.

Got some pondering to do...

Isn't this dangerous? In the hospital when they do surgery or when first diagnosed, they use an IV drip of insulin which is immediate in action, but they also have a corresponding dextrose drip. So you can immediately correct with the dextrose if low. If you dropped too low from the IM injection of insulin, glucose would take about ten minutes to start bringing your blood sugar up. Would you have enough time if the dose was too high? Also, do you need more, less or the same amount of insulin when injecting IM? I have heard Dr. Bernstein does do this. Also sounds painful.

That's interesting, Dave. Makes sense, too. A healthy pancreas releases insulin much more quickly than our sub-q shots. From your description, maybe it would even work better to shorten the pre-bolus time to 15 minutes.

As far as more risk goes, we live with risk with every insulin dose we take. It comes with the territory. As long as you have fast-acting glucose handy, what's to fear? Can you imagine the health benefits of keeping a high percentage of BGs in the 75-95 range? Not to mention the physical and emotional benefits as well?

I look forward to more reports on this. As a result of your IM discussions, I'm using more IM corrections, some of them as little as one unit. They do work faster and I haven't over-corrected, even once. IM shots are a great addition to my kit.

Some things I ran across with a quick google search. Some researchers say that, while IM injection can cause a more normal physiological response, the insulin effect may not last as long as subq. Another says that IM injection results vary by amount of muscle activity after injection: rest or light, moderate, heavy activity. These variations, they said, were not evident after subq activity. This latter is from a 1991 study so I don't know if it has been disproved or not:

I don't know if any of these things are true. Just wonder what your experience has been with variable activity levels. If you are on a pump, you likely can't judge the duration of IM injection effect since you continue to get your basal insulin.
Also, supposedly more painful...

Where do you get your 12 mm insulin injection needles?!

IDK where he gets then, but I know walmart sells them over the counter.

this is really interesting. id probably be too chicken to do this, but how painful are the IM injections?

Would you like to describe your IM injection technique? I am quite curious? I’m a very lean guy and spend a lot more effort in finding fatty tissue to inject to…

My experience with IM injections is that they are more variable. It may that I don't know whether I get it in a muscle or hit some veins or what, but it seems to vary more than subcutaneous. And we have to remember, with an experiment with a sample size one, the result has no significance. You really need to do this many times to gain any confidence that it is better for mealtime boluses. Personally, I'm a bit skeptical that a bolus which is short, sharp and fast acting will match a low carb high fat meal that usually is best matched by an extended or dual bolus.

States vary as to whether you can purchase needles OTC.

No way your getting a IM injection with a 12mm syringe (a 12 mm needle is less than a 1/2"…you need a 30-36mm needle.
After feeling the pain of a few real IM injections and you’ll be singing a different song…JMHO…:slight_smile:

Wow! BD says you even need a 7/8" to 1" for an infant. OUCH!

Bernstein recommends using the 12.7mm 1/2" syringe and injecting in your deltoid. I find my quad has very little bodyfat and works fine. I don't seem to have any issue with 8mm needles on my quads. This study shows that arms and legs seem to have more like 1-3mm of bodyfat and that it can vary significantly.

Obviously it varies from one person to another… I am certain I could injec IM into my biceps with far less than 12mm…

Specifically where are you injecting? What site?

Dangerous? That's a loaded term.

First, IM is not IV. IM has gradual absorption characteristics just like subcutaneous, just about twice as fast. This makes all the metrics for insulin -- time to onset, peak, tail -- about twice as fast. Also, because of this the peak level in the blood is higher.

Bottom line, it works faster, bigger, and clears sooner. However, it's far from the near instantaneous action of direct administration into the blood through an IV or venous injection. As such, IM can be safely used if you learn how it's different, and adjust your calculations/practices accordingly.

Worst part is the long needle is a bit of a put-off, and it hurts a little more than a subQ injection.

I'll say this though: I would not do this if I didn't have a CGM.

[variability in effective duration, muscle activity impact...]

Yes, I've found both of these to be true. I've had to adjust my parameters in Glucosurfer to account for the shorter tail (I use GF to manage insulin when I'm doin IMs).

The biggest thing I notice in terms of variability, however, is speed of action depending on the muscle activity. I have a desk job, so my delts get more on-going activity than my quads, so I usually use them.

Even if totally sendentary (lying on the bed reading or something), IM injections still are significantly faster than subQ.

Where do you get your 12 mm insulin injection needles?!

Since I pump, I don't have pens. I just buy the cheap disposable syringes at Walgreens... 10-pack a bit over 3 bucks. However, BD does make 12mm pen needles too, although mail-order is pretty much the only way to get them.

Not bad at all. It's hit and miss, just like subQ -- most of the time it's just a minor poke, every once in a while you stick it in and hit a nerve or something, and wince.

I found the most important thing is to make sure the needle stays aligned at the angle you insert it (usually 90deg to the skin surface) the entire time its in there. Swinging around (like a pendulum) hurts a lot, and you can easily visualize what's going on when you do that.

I'm crazy, so I jam the thing all the way in and hold it so the skin surface is depressed into a little concavity about 1/4" deep pushed in by the bottom of the syringe. Inject like a subQ -- slowly -- then let it sit for a bit before removing -- this help prevent bleeders. When done, yank it out in one quick pull, cover the spot with the alcohol pad you used to clean it, and gently push and rub the injection spot for 10 seconds or so.


If I have a big dose (I have IR), I'll split it into two sites. I took a 40U correction over the weekend (don't ask), 20 in each deltoid, one syringe filled to 40.

You really need to do this many times to gain any confidence that it is better for mealtime boluses

Spot on!

And indeed, that's what I'm doing.

Yes way. There's no question.