Bad Reaction to Insulin by Infusion?

Hi all, I started pumping two weeks ago, and I’ve noticed that within 48 hours, sometimes 36 or less, my infusion sites become red and inflamed and sometimes I have a noticeable bump under the skin where the site was, though this seems to be going away within a day or two.

Has anyone else experienced this? I never reacted to insulin before with MDI (I’m using Humalog, BTW, as I have been for many years), and am very wary of starting to accrue scar tissue or other problems from repeated inflammation.

I started using the Silhouette infusion set and when I first got the reaction, my doctor, trainer and I thought I might be reacting to the Teflon cannula, but I’ve since tried a Sure T set with a metal needle a couple of times with same outcome - at 48 hours, red and inflamed and painful to pressure, and with a bump under the skin.

Any and all thoughts and advice anyone has would be much appreciated - I’m afraid I could be required to give up pumping even though it’s been amazing to finally get my dawn phenomenon under reasonable control after 25 years.

Could it be IV prep carried under the skin by the canula? Try changing your prep routine. ? Or maybe the adhesive? I have no real idea. I to thought of the teflon, but that wasn’t a help. Sorry, maybe someone else has an idea.

I had something similar happen when I started pumping, I was also using Humalog and would get a knot at the site within a day or so and the insulin would tend to seep back up instead of getting absorbed. I think I was having some type of reaction to the Humalog, On MDI, each shot site isn’t “exposed” to insulin for as long as it is when pumping, so I just didn’t notice it before. I tried a couple of different infusion sets, but had the same problems. I switched insulin types (now on Apidra, but also tried Novalog) and the problem went away so you might see if your doctor could give you a sample bottle of something else

I’ve tried both the IV prep stuff and just plain alcohol allowed to dry before the set is put on, so I don’t think it’s that, but thanks, good thinking.

Very interesting! I’ll ask for some new bottles.

Another thing you might try is just to put a set in by itself, not hooked to the pump and see if you still have the issue. That should let you know if it is an insertion set issue or an insulin issue…

I’d probably loose that one… wonder if it is the adhesive…

I had similar responses after starting on the pump. Mine was an allergy to the adhesive. Since then I use a barrier prep (Cavilon) with no problems.

I also wonder if you are on a large amount of insulin. If so, it might be a reaction to it, since with MDI, you are rotating your injection sites and one site doesn’t get all the insulin…Good Luck!


The insulin seems to me more likely the culprit than the adhesive - I don’t react to the adhesive in the CGMS pads for either Minimed or DexCom with nearly the same severity and certainly don’t end up with bumps under the skin from this, though a skin prep still seems worth looking into. Thanks again to all for all the info. Lots to consider here, and please do keep them coming.

Yep, and I’ve been on the same exact insulin (Humalog) 5-10 shots a day for years. But, and it’s a big but, that’s one shot in one site, then on to the next one and not in the same place again for at the very least days if not weeks. Hmmmm.

Have you tried Scott’s suggestion yet (use a set without being hooked up to the pump)?

Any input from your endo or MM?

You might also try a number of days where you change the site every day. My wild thought on this is you might get your body to slowly develop a tolerance for the infusion sets.

Fair Winds,

My endo called in an Apidra script just now, the pharmacy didn’t have it but will have it by tomorrow and I will try it starting with my next reservoir!

BTW, for anyone who might have been wondering, the Apidra was night and day from the Humalog - I’ve had one or two unhappy sites since then, but generally dramatically better than the Humalog with the Silhouettes.

it sounds like you’re allergic to the teflon set. I would switch to a steel set as soon as possible.

I had the same problem when I started pumping. Turns out I’m sensitive to the adhesive on the insertion set. I tried various barriers, and both IV 3000 and Tegaderm work for me. I use Tegaderm patches now because the IV 3000 doesn’t stick as well. Just insert the site through the barrier.

You may have to try a few different barriers to figure out which one works for you. As for the bumps…they usually go away. Sometimes they may be from the site being in so long, but I think sometimes it’s just from the back of the site pressing on your skin…the back of the site isn’t flat, and I think it makes that bump just like you’d get on your skin if you slept on top of wrinkled sheets.