Infusion set allergy

Curious to hear from other people who developed an allergy to the cannula in their infusion sets (but not the adhesive) and how long it took to “develop” and also a few other questions …

I am 99% sure I’ve developed such an allergy. I’ve been pumping for 4.5 years and for the first year or so used Cleos, then switched to Comforts because they were packaged flatter and easier to carry around. I’ve always had a bit of an issue with infusion sets, I think, and I’ve always required more insulin on the pump than I did before, which is kind of the opposite of what most people experience. I found that after about day two my blood sugars would rise, so I started changing them on day two. And I would often notice a site would get itchy near the end of day two and there would be an itchy lump (but not an infection) when I removed it, and it would remain itchy for a day or two after taking it out. But it was never that big of an issue and overall my control on the pump is so much better than on shots, I would never want to give it up.

So, anyway, over the past six weeks or so my blood sugar control just went crazy. First it was just really inconsistent, and then I was just constantly high. I had to up all my pump settings again and again and was still high. I also noticed my pump sites getting really itchy on about day two, to the point where I literally could not stand it anymore and began changing them early. Then they began to get itchy just hours after insertion, and I started changing them almost daily, and even after only a day they would be bright red and have a giant “hive” surrounding the area where the cannula was …

And I thought this was just ridiculous. The other day I ordered Contact-Detach infusion sets from my pharmacy and am hoping they come SOON. The other day I also taped an uninserted set to my stomach to see if it was the adhesive causing irritation, and after two days the skin was fine, not itchy at all.

Then tonight I just got so fed up with the insulin seeming to hardly work at all, that I decided to do a shot to make sure it was actually a site issue and not an insulin issue (I just switched to Apidra about six months ago). Using my new “higher” settings (which are nearly double my old settings) I corrected a 9.9 (178) and within an hour I had dropped to 3.1 (56)!! So it’s definitely the sites, and judging from the fact that I had no problems with just the adhesive, it’s probably the cannula.

So, anyway, not sure what the point of this is other than to complain about my immune system seeming to find yet another thing to needlessly attack … Are there any tests for “cannula allergy” I could get? If I am allergic to pump infusion sets do I need to be worried if I ever needed an IV or something like that, or is that made of some different material? If I get a CGM in the future (which WILL happen at some point!!!) might I have any issues with the sensor bit (not adhesive)?

I found some information about allergies and pump bumps on another website. I often have a pump bump and itching after 3 days using a site, but rarely do I find my BGs are elevating. Hope this is of some help to you.

What Are The Possible Solutions for Site and Skin Problems?
Note: This is taken almost directly from Pumping Insulin - Chapter 22. If you are having ANY problems with your pump, see if the book has a solution. It is not called the pumpers bible for fun!

Anytime you put something in or on your body that is not supposed to be there, it invites the potential for problems.

Several aspects of insulin pumping can cause skin irritations or allergies for diabetics. Sources may include the teflon cannula, metal needle, site adhesive or adhesive materials, and oddly enough even insulin.

Allergies and Irritations

If you are dealing with itching and irritation with your infusion set, it is pretty easy to determine the cause with a little investigation. Most often, the irritation pattern will match the source of the problem. As Walsh states" the itchy area, irritation, or redness forms a pattern with the same shape as the tape, dressing or infusion lines that causes it" (p.239). If it is the actual cannula causing the problem, the irritation will instead be at the point where the set enters the skin.

If you develop an allergy, some possible solutions include trying one of the many other infusion sets that exist for insulin pumps. You may also want to consider using some sort of protective dressing such as Skin Prep or IV3000. Side note: Somewhat ironically, Skin Prep is so far the only thing I have had a reaction to while pumping


Signs of infection include:
redness and inflammation
unexplained high blood sugar

If you experience any of the symptoms listed above and suspect an infection, remove the infusion site. Gently squeeze the site and note the fluid that appears. If bright red blood appears, you likely just had a bit of bleeding under the skin. Insert a new infusion site at a new location and you should be fine.

If the fluid is whitish, discolored, or appears to be pus it is likely an infection. In four years of pumping, I have only had one possible infection which I treated with over-the-counter antibiotic ointment.


On the Top of the Skin
Sometimes during the insertion of a infusion set, you many hit a small blood vessel near the top of the skin, resulting in a small stain observable under the tape or dressing. If the site is not painful, inflammed, or ineffective (and you are not bleeding all over your new white pants), the site is fine and you may continue using it as normal

Inside the Infusion Tube
If you can observe blood inside the infusion tubing, it actually means that you are bleeding at the tip of the infusion site. As you can imagine, this may dilute the insulin that the pump is delivering. The best treatment is to remove the infusion set and insert or re-insert in a new location.

Under the Skin
This will feel like a sore or a bruise. The lump may appear normal in color or slightly red. Again, this dilutes the insulin your pump is delivering and the best treatment is to remove the infusion set and insert or re-insert in a new location. This sounds rather gross, but, sqeeze the lump to “extract as much matter as you can” (pg. 241). See the section on infections to determine the best course of action based on what appears.

Pump Bumps

Boy could I write the book on this one - I have one of these almost every time!

A pump bump (ignore the ridiculous name) is the “slightly red, raised, pimple-sized spot found at the infusion site after an infusion set is removed” (pg. 242). The spot gradually disappears in the hours or days after you change your infusion set. These bumps may be caused by a reaction to the coating on the outside of the needle or cannula or a reaction to the preservative and other trace chemicals found in insulin.

There is really no reason to treat a pump bump, but if you would like to reduce the chances of getting one, you could cover the infusion site with Skin Prep or insert the set through IV3000 or other similar product.

Pump Hypertrophy

When an infusion set is used repeatedly in one part of the body, that area may enlarge because insulin causes cells to grow. This may cause a lump, or hypertrophy to occur at the location. Be sure to rotate infusion sites through all usable parts of the body including but not limited to the abdomen, backside, and legs. Avoid a spot in which you suspect hypertrophy for 3-4 weeks to allow healing to begin.


“Poor absorption of insulin at infusion sites due to scarring occurs, but it receives an excessive amount of blame for control problems” (p 242). If your blood sugar began rising immediately or soon after a site was inserted, poor absorption due to scarring may be one of many possible causes (kinked set or any of the problems listed above are some of the others). If your blood sugar did not begin rising until eight or more hours after inserting the site, scarring is not the cause.

Hope this helps clear up any confusion and help you continue your hassle-free (or less) pumping!


I don’t know that I have a true cannula allergy, but I also experience the itchiness toward the end of day 2. So I alternate between Sure-T (which is a steel cannula) and the Silhouette (which is a teflon cannula). I have a suspicion that for me it is the teflon cannula that is the most troublesome. I don’t have near as much trouble with the Sure-T as the teflon cannula.

I have contact-detach sites (same as the Sure-T for non-Minimed pumps) on order so I am hoping this will solve the problems. I have noticed my sites seem less irritated in general now that I am changing them every 1-1.5 days, but I can’t keep that up forever, and my blood sugars still seem ridiculous to me. I’m not sure if there’s any way to “prove” that I have an actual allergy to the cannula but I think my body is definitely rejecting them (and I also have a severe food allergy and many seasonal/environmental alleriges, so it wouldn’t surprise me if I am now also allergic to the cannula).

Put teflon set in - but do not infuse any insulin. leave it there up to three days. Then do same for steel. If the teflon gets sore/itchy etc, and steel does not and you know no insulin was used in either, then high probability you are sensitive to teflon… many folks are.


I am having this problem RIGHT NOW. What worked? Did changing sets work? THANKS!

will try! thanks!

I have food allergies, seasonal too. But I've been pumping since 1992.
How could I all of a sudden become allergic?
My sites I can only stand for 12 hours max. (irritated) so back on shots :(

Ugh, this sounds like my story too, except I dont get hives (yet?), and my sites hurt more than they itch, but the rest of it... unexplained and inconsistent highs, irritated but not infected sites, and it doesn't seem to be the adhesive because its generally not ON my skin, its UNDER.
Did you find an answer? Or at least find a way to make it more bearable? After reading this I've got a few ideas on at least how to determine which part of my system is causing a problem, and I guess I'll just have to go from there...

For what its worth though, I very happily use my CGM (Dex G4) and have had ZERO issues with the adhesive, the hole in my skin, or the piece that stabs in so in. That almost just makes the other issue more mysterious though!

I have a Dex COm and do okay with that tape also.... but back on Lantus with the pump tape issues

We are dealing with this now. About a month ago, we noticed highs unless we changed our boy's site every 48 hours, promptly. (Previously we had gone 72 hours with no problem.) Then it was every 36 hours. Then every 24 hours. Now, this week, we have to change more than every day. That's a lot of kachunking into the tender bottom of a child. This is with Inset 30.

I'm trying to switch over to the metal sets. Apparently we need to wait for Animas to have a sales rep bring the metal ones to our endo office, and then wait for Animas to schedule a training in the use of the metal ones for us.

Meanwhile should we switch back to Lantus? The allergic reaction is getting (exponentially?) faster and more severe. Oy!

Hi Katy,
I had the same issue. I also tried putting tegraderm tape on my skin, and inserting the pump catheter thru that. But still the red inflammed rashes and swelling at the site- looked like playdough kind of, hard to explain.
I used the metal ones for years before the new ones came out. Don't buy a whole bunch until you try it first.... I was in high school then, and more active... the metal ones I was constantly aware of- not comfortable.
So, I'm back on Lantus.
I miss my pump's convience, but not the skin issues and high bg's!
Please share if you find any other solutions!!! Thank you so much! Maria

I still haven't really found a solution, although I am still pumping. I've switched to the metal sets, but I am allergic to them as well because I'm allergic to nickel. But they are more bearable than the cannulas were, especially if I take an antihistamine every day. If I don't take an antihistamine, then they get a lot more irritated.

The other week I tried a cannula set again, just to see, and had the same type of reaction (worse than the metal set reaction), so I definitely have an issue.

Lately the highs and inconsistency have come back, and in the past two or three months I've spent most of it really insulin resistant (taking 100+ units of insulin). Insulin resistance or sites not absorbing? Hard to tell. My schedule is insane lately, so part of it might be that, too. Things should calm down a lot in a month when I am done my master's degree and one of my volunteer roles.

My biggest problem with the metals sets has been the adhesive. The adhesive hardly sticks to my skin at all. But all the options I've tried to take to make it stick (Skin Tac, Tegaderm, Band-Aids) result in unbearable irritation that sometimes lasts for literally weeks after removal! Using just the metals sets with the built-in adhesive, they get a bit itchy and irritated but it's bearable, and only lasts a day or two after removal. So for the time being I've been doing that and just changing sites early if they fall out (which they do regularly).

I have a lot of allergy issues in general right now that go beyond these pump issues. Food allergies, asthma, an allergic inflammatory condition in my throat (eosinophilic esophagitis), and horrible seasonal/environmental allergies, some of which are pretty out of control right now even with medication. I'm seeing an allergist next week for food allergy testing, but I'll probably ask him if I can make a follow-up appointment to see if he can help with this pump stuff. I'm also hoping that if we can eliminate some of the foods I'm reacting to, that my body's reactivity in general will calm down, and that should help the site problems, I hope!

You sound just like me- lots of food sensitivities, autoimmune stuff going on.
I switched to Lantus at night and Novolog during the day and am doing great. The one PAIN about it is: I have terrible high bg;s from 3 am- 7 am.... and if I take the Lantus at midnight, I crash by 2 am. SO.... I actually take my Lantus at 2 am. Luckily I just fall right back asleep.
I'm also working on inflammation with diet and supplements. I did an elimination diet and found corn, yeast, soy and wheat to be biggies. You can google "AIP" or Autoimmune Protocol diet- there's a facebook group with it also.
I hope you don't have to do Lantus like me and can just do it at bedtime~
Once I get my inflammation down, I'm going to go back and try the pump again.
This same pump issue happened last year when I had a Lyme flare up, and then I went back on thepump..... fingers crossed that this is temporary!!!!