Intravenous & Intramuscular Injection


I have heard some people suggesting that IM injections speed up absorption of insulin for correction bolus, but after some experimentation, I haven’t noticed a measurably faster action. I did a little further reading, and most of the research i ran into suggests that the action of novolog/humalog is not consistently sped up by intramuscular injection.

So i was wondering if anyone has experience injecting small corrections intravenously. If so, i am interested in what sites, methods, and general guidance you might have. I know IV injection is not a normal way of administering insulin, but I am of a mind to think the fastest possible action is ideal for correction, to minimize unexpected interference with meal boluses.

Only with R, which works quite a bit faster. Someone on another site had explained that the mechanism by which the 'logs work faster doesn’t work faster IV.

I think you will find out that an intravenous injection of insulin witha syringe, even a small amount, could be potentially hazardous to your health ,or even fatal; if the meausred dose is not set up exactly. The type of insulins we use are designed for injections into either adipose tissue or intramuacularly. I for one, do note a faster level of absorption in the leaner, more muscular areas of my legs anand or arms.

I use a syringe rather than a pump when I need to correct a bad infusion set high; and I do, on some occasions, shoot into the leg muscle. I do have a CGM and can watch the trends; However, I never never, never , inject into a vein:Why do you think that people presenting with DKA and very high blood glucose,are put on an iv drip of insulin in a slow, metered do while in an ER or a hospital?..Don’t even try it at home!!! I am serious…

God Bless,


I agree it’s dangerous however I did it all the time for years.

I understand the disclaimer, but I don’t agree. They are put on a slow IV drip, because it gives those treating the patient greater control over utilization of the insulin, they can alter the rate of the drip manual, instead of relying on the action of a particular insulin variety. Treating DKA is something that takes time, and requires more dilligence than normal glycemic control. I would think a shorter duration would be considerably LESS dangerous in the event of an accidental overdose, as the danger our low BG is compounded by the duration.

Of course I could be wrong.

The injection of a basal/long-acting insulin should be subcutaneous, but a rapid insulin can be taken IM. The injection into muscle can be highly variable due to differences in blood flow, but it can enable a faster onset, particularly for R. Dr. Bernstein even has a video on how to do IM for fast corrections. I would agree with Brunetta, injecting in a vein is not a good idea.

ps. The reason a basal should not be injected IM is that it can “act like a rapid,” the formulations intended to slowly release the insulin don’t work and all the sudden your basal of 30 units is actually a rapid bolus of 30 units.

Right. I understand. I would never considerer IV or IM for anything other than correction, as the purpose of bolus and basal administration is to slow down absorption to mimic natural insulin levels. I do not see the risk of dangerous lows being any greater with IV administration though, as long as it is only for correcting already elevated BG. I never correct to anything below 180 anyhow. The biggest risk I see, is that administering anything other than regular will decrease blood ph, which is no good if you are trying to correct in the presence of ketones.

I am a pretty careful person, this is the only reason I am even interested in IV injection. Unless there is some other reason, aside from the attack and duration the insulin (which is why its appealing), then I think its an option worthy of consideration.

An accute short lived low seems like it would be better handled by glucagon release than a prolonged low, since it is both more likely to trigger it, and can be corrected in a shorter amount of time. I really do not understand why IM is more viable as a correction method, if it depends so heavily on local circulation. Predictability is important.

I would usually note a drop from 300 to 50-70 in about 1/2 hour? A lot of times, I’d test at 15 minutes and be at about 150 but already getting the visceral symptoms of severe lows, sweating, a bit rattled, etc. Perhaps the meter wasn’t quite locked in either as I’d be testing in fingers “upriver” from my big elbow veins? I would say its not to be trifled with but, as long as you have some carbs lying around and perhaps a ‘helper’ in case you overshoot, it should be ok. IV shots were pretty predictable too. I haven’t ever had the urge to try it with my pump but that seems to keep things managed a bit tidier?

Dr. Bernstein looks so unhealthy, and right now I am freaking out watching him give himself a shot, but I would love to lower my highs a lot faster, but ouch.

After 44 years still not use to shots.

You know he is now 76 years old? That video was made when he was 72, I actually think he looks pretty lean and muscular for a 72 year old man. Why do you think he looks unhealthy? I always wanted to look lean and muscular, maybe I need to reexamine things.

I have never tried IM injections with Humalog, I don’t think I’d try it. One time I accidentally injected Lantus into my bloodstream and it was a nightmare! I dropped about 50 points in 10 minutes and kept dropping. I had to drink almost a whole 2 liter of pepsi before my blood sugar climbed back to normal. It was scary and ridiculous.