Site location and variation in insulin effectiveness

Do any of you notice a significant difference in insulin effectiveness based on site location?

I don’t mean scar tissue, but arms, legs, stomach, hips.

Since going low carb, I’ve noticed a very significant difference in basal needs, in particular, between sites. When I switch to my stomach I invariably end up having to run a -30% or so basal rate to not go low for hours on end. When I use my arms or legs, I have to run a +30% basal rate or higher and often still go high for hours.

In some ways this is good because it explains yet another piece of the puzzle I’m dealing with as far as blood sugar variability is concerned. But in other ways it’s extremely annoying…

I do all my sub-Q injections in the abdomen. I have 18 sites that I rotate through in sequence and I really haven’t seen any discernible difference.

The only difference I do notice is when I do IM injections in the deltoids. Those are noticeably quicker acting, which is why I use them when the occasion calls for it.

How long have you been using insulin? I’m guessing that, if you continue doing all your shots in your stomach long-term, you’re going to eventually run into problems with scar tissue.

After 10 years of pumping, I’ve recently been told to avoid my lower abdomen. I still use my upper abdomen and arms, legs, hips, butt (which I used before occasionally, but did prefer my stomach).

It’s been since rotating more than I’ve noticed these blood sugar variations based on site. I’m not referring to variations within the same site, like changes from one spot on my arm to the other or from one leg to the other, but rather differences in each site on the body (stomach vs. legs vs. arms vs. hips vs butt).

Because I often insert my infusion set one-handed (and also probably because I’m visually impaired), I find it difficult to rotate precisely among one site location like my arm for any length of time. It’s hard to precisely place a site exactly where I intend (it could end up a few centimetres off the mark), and I can’t use those little sheets of dots that some people use as site rotation recorders.

Perhaps, perhaps not. Like everything else involving this insane disease, it depends on the person. I know longtime PWD (decades) who do not have scar tissue issues, and others who do. I can’t prove it, but I firmly believe that consistency and discipline make a difference. With my rotation, each site goes a minimum of two days before being reused, and since no two injections land on precisely the same spot anyway, so effectively it’s much longer. Time will tell.

Anecdotally, though, I do seem to hear FAR more scarring complaints from pump users than MDIers.

My problem isn’t so much scarring as “lumpiness”, which is probably some sort of precursor to scarring. In either case, I was advised to avoid the area for a bit. But I’m 25 years in to diabetes (10 years in to pumping), so I’m not surprised that it came up eventually. I think that having a foreign object sit under your skin for several days is bound to lead to more scarring than an injection (especially since I use metal sets, not the soft plastic ones).

Makes perfect sense

I believe the anecdotal evidence (that’s an oxymoron, isn’t it?) is also Dr. Bernstein’s opinion. I have heard him say in an interview (or other recording) that he does not like pumps for that precise reason. Though I’m not specifically a Dr. Bernstein “follower” (as you know), I assume that he speaks from experience with a large population of patients.

That said, I use a pump because it solves multiple problems for me - none of which has to do with convenience, though that’s nice, too. I do worry about scarring – with my luck and albeit limited experience with diabetes, I assume that I will somehow be affected by ANY possible issue or side effect of treatment (as I have, thus far), so I try and rotate both areas ans sites within areas. Gave my stomach a long rest, but am now using that area again, because I feel the need to give my thighs a rest, etc…

In response to the OP, @Jen, I have noticed no difference in effectiveness or insulin based on site. I have used stomach, arms, thighs, “love handles,” calves, and even chest – I have seen no need to adjust doses or basal rates for ANY of those sites. I do notice a difference in the rate of absorption/time of action between sites; however, the difference is not huge for me in most cases. Note: my absorption seems to be slower than what I hear from most on this forum, so my experience is likely different in this way as well – who knows?

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I’m one of those odd ones like David, I have used my abdomen religiously for years both MDI and pump with no problems. I also use a soft plastic cannula too. My pump sites are very uncomfortable and I get awful absorption in my legs. My guess is my legs don’t have a lot of fat on them, and especially on a pump I use my legs, I tend to get crimped cannulas. I used to use my arms some for MDI, and never really noticed any problems with absorption but in all fairness, that was as a teenager and just not giving a rip so how great my absorption was…who knows. I say I’ve been primarily using my stomach and being diligent with rotation wow probably 10-15 years easily, knock on wood no problem. I don’t mind using my arms for MDI, but I think trying to get an infusion site in would be a bit awkward especially in the fatty areas of my arm. But I may try it one of these days.

Arms/legs could be problematic depending on the person and how muscular or how much body fat they have. If one is more muscular, they should have a more rapid absorption rate.

I’d never used arms for infusion sites until I did a short period on Omnipod. I didn’t like the 'Pod so much in the end, but it did open me up to trying arms for infusion sites. Now, I use them a fair bit, even with a tubed pump (Animas Vibe), and have been quite happy with the results.

I found MDI injections were easy enough to do in the arm…but infusion sets are a little more awkward, lol not enough hands to get to fatty part of arm and mess with the infusion set too. I could see it being a decent spot for Omnipods…I think for me, being on a tubed pump and having the site on my arm would be difficult. LOL but we all kinda find what works best for us.

I don’t pump, but I certainly notice that I seem to require more insulin if I inject in my thigh versus my abdomen. The exact same meals and same amount of insulin when given in my thight always in my experience ends in higher blood glucose than if I give the injection in my abdomen.

Because of that I typically avoid injecting in my thigh and try to rotate only around my abdomen.

I was always told that the fat on stomach and arms absorb faster, whereas fat on legs/butt/hips take longer (and I have enough fat on each that I’m definitely not hitting muscle unintentionally). I’m on MDI, and I don’t use my arms, because I tend to get awkward bruises there, but I tend to use my stomach for Humalog and my thighs or butt for Lantus.

That would fit with what I experience. My stomach works the best, arms and legs decent, hips and butt seem to vary somewhat. I have lots of fat, yet somehow a fairly large portion of my sites do end up hurting and bleeding for some reason.