My insulin seems to "go bad"

Do you ever experience a sudden jump in BG after wearing your pump for a few days.
I have found that I can’t fill my pump because the insulin seems to lose effectiveness
after I have used the first 120 units or so. I only fill it halfway now. I’m experimenting
with keeping the pump outside the covers at night, not keeping it in my back pocket
if I can avoid it… etc. as I think it is the heat that must be the culprit. Anyone else
with this same kind of experience. I’ve had sudden high blood sugars a number of times
and the only variable that brings me back to normal performance is changing the insulin.

Do you wear your pump close to your skin during the day?

May be some felt between the pump and the body.

How many days are you using the site for…?

Some people… can only use a site for 2 days, before their BG climbs up… its probably not the insulin…

You might need more frequent site changes… or it could be the set/insertion… Try changing the set every two days a couple of times… If this helps. you can probably get away with using the cartridge for two site changes, mebby more, but YDMV… If you are using a metal cannula set… you REALLY should be changing every 48 hours… The one advantage is if you dont have an adhesive sensitivity/allergy, you can usually get away with less adhesive products… if im only using a set for 2 days, i can usually skip the skin tac/skin prep… and just use alcohol/CHG (hibistat)… let dry and slap a tegaderm down and be done with the prep :wink:

I noticed the same thing happening to me a while ago and my pump trainer informed me that the plastic of the tubing and reservoir begins to breakdown and dilutes the insulin. I’ve been making it a point to change my site every 2-3 days. That has been extremely helpful. Good luck!

I agree with this. I change sites every 2 or 2.5 days because if I leave it in longer than that my BG climbs a lot. It’s gotten better since I switched from Humalog to Apidra, and also since I’ve moved sites to areas that haven’t been used frequently. But I would look at your infusion sites rather than the insulin suddenly going bad.

Try using Novolog instead of Humalog. I was told it’s “heartier” it isn’t as affected by temp. I still use syringes but I kept on the with the Novolog and haven’t had trouble with it loosing its umph.

Lex, I also was having problems with Apidra breaking down fast in my cartridges. When it is hot out, I have to change them every day and a half. The Animas clinical manager for my area also told me that the cartridges should be changed every 2 days.

As other people have said, usually the culprit is a site that has gone bad, not the insulin. I hope you are able to figure it out!

I agree with the site maybe causing you some trouble too but my and Humalog just didn’t agree. I ran “HI” alot of times with it. When my Dr changed me back to Novolog I have been having a better experiance with the bs’s

As usual, great feedback with differing conclusions. In trying to come up with the
consistent variable that is thwarting my otherwise predictable blood sugar
I have been changing the site first. Usually I conclude that it’s something I did
or didn’t do and up my dose, and then after chasing the high all day with more
and more insulin, I change the insulin, too. Immediately I get positive results and
the normal dosage brings my blood sugar back down. My diet is pretty steady
and I’m pretty aware of how stress and exercise affect my readings. I use about
13 units for basal and 13 for bolus a day. I do change my site about every two or three
days. I haven’t noticed leaving it in longer creates any major impact except the site
begins to get red and sensitive. I’m on humalog. Does any of this info affect the debate on
whether or not the insulin is degrading or not? Or the line? Thanks for your feedback, guys.

I have been researching the same problem since June. I use the Solostar Lantus pens that are disposable so there is a pump right inside the insulin that pushes it forward. The first insulin used in the pen is ok but the closer to the pump I get the worst I feel and the more insulin I need to take to get the same effect. I’m on my 7th cartridge that I have had trouble with and it applied to all of them while I had no trouble with Lantus for the 5 years prior to that
I asked my doctor whether I was developing a resistance or allergy to the insulin, so I said I feel ok taking repeated doses of short acting insulin so perhaps I need to be on a pump. So he said you are the type of person who can do it.
I got the answer when at my first seminar to learn how to use a pump, before I switch.

The seminar leader said plastic degrades insulin even after 3 days.

The fact that you are having a problem on the PUMP means even more that I don’t want the bother of a pump as the plastic degrades insulin problem is also evident there. You can find others have talked about it, if you search for the right words. One user said even in a hot shower the insulin is made worse because of the heat.
If you take insulin in and out of the fridge the temp change degrades insulin the manufacturer told me.
It is obviously because there is plastic inside the pump that helps control the release, just as there is a plunger in my disposable Lantus pen.
So I am absolutely certain this is the reason. It has been a major problem for me so long I have spent hours researching it.
So it is not the type of insulin that matters but the plastic inside.
So thank you a LOT for your insight because it means a pump is just as much a problem as the disposable pens. It is not the insulin that is at fault, but the plastic.

Well I am glad you clarified that about the PUMP…as I am not on one yet and just in the deciding stage, where I have to attend 7 seminars and I’m reading the Walsh book. But in my Lantus solostar disposable injector pen there is a plastic plunger that pushes the insulin forward. And the effect I have had of needing more insulin nearer to the plunger is evident to me.
So my plan is to get the 3ml vials of glass and just use them with a syringe. I can’t afford to throw out three more already puchased cartirdge pens so I have to wait. I feel so much better even when I take NO insulin and starve all day and take correcting doses of Humalog, so I know the Lantus is poisoned by the plastic.

When I Googled Polyfin Infusion Sets, it came up with MM stuff. That might be true for Minimed, but the Animas Clinical Manager told me that with their sets, insulin does break down after 2 days and they recommend changing them at 2 days. That also might be the reason they only make smaller cartridges.

I have a friend that uses Lantus in the glass vials. She is having a problem with it breaking down after 2 weeks.

I recently started having a problem with Apidra - both Lantus and Apidra are made by the same company. Someone used a search term “problems with Apidra” to land on my blog - not sure why because I never wrote about Apidra problems. I decided to Google it and I found another blogger that wrote about her Apidra breaking down after 10 days. That is about when 2 vials I had died.

It might be an insulin problem that has nothing to do with the pen!

Aha moment. Yes, Janina, I realized, without realizing it, that temperature may be playing a role and filled the reservoir for my pump with insulin right out of the fridge instead of following my usual protocol of letting it come to room temperature in order to
have fewer bubbles. Perhaps the temperature variations that the insulin goes through are impacting the outcome. Thanks for the information. I really feel confident that it is a degraded insulin. All facts lead to a fairly obvious conclusion. I’ll keep experimenting and let you know. I appreciate your dedication to doing the research.

Thanks for both Kelly, yes my first problem happened before I switched to the Solostar, when I was using the 10ml vial format that I’ve used for 5 years. I always knew I was using it beyond 28 days but I kept it in the fridge in a juice sized tiny glass on the door shelf…one each for Lantus and Humalog and I place the syringe beside them and keep using the same syringe even more than 60 times, but have had no problem for 29 years.
When I complained once on a 10ml vial it had seemed to not be good within just a few days, so they replaced it. I then got a vial that did last fine for 2.5 months as usual, but then I decided to go with 5x3ml and they last me 2-3 weeks each, so I am within the 28 day warranty.
I plan to take a longer time to decide on a pump and try the Lantus in 3ml size but also keep it in the fridge…I am certain that is the difference that I used in the past 5 years. It means just take it out long enough for the injection and put it right back so there’s little temp change.
And thanks Carolyne for asking the question because I may have already asked it in a different group, but got no feedback, or maybe I forgot to put it up,…I’m just active on this site for 6 weeks although I did join in July. So I am a newbie on using the site.

Try novalog. Technically humalog isn’t approved specifically for pump. In us. It can crystalize in the set/tubing/cannula but usually when its too hot. Also try for every 2 not 3 for a bit

Janina, my experience is with the Mini Med pumps, which I wear part time. I use the Sure-T infusion set, which has a metal needle. The Sure-T instructions say to change the set every two days, and I assume that means also the plastic cartridge which holds the insulin. With a good site, I have had no insulin problems traceable to the insulin in the cartridge following those directions.

Like most people, I’ve done a little experimenting: I have changed the needle part of the set, but reused the cartridge with leftover insulin for another site. When I have done that, I start running a high BG at 1 1/2 days (total of 3 1/2 days for the cartridge/insulin). If you follow the directions on a Mini Med (can’t speak for any other pump) and change the infusion set and cartridge every two days, there should be no problem with the plastic cartridge.

Sometimes you can arrange with your doctor, CDE or pump reps. to try different pumps and sets before deciding on one or none. Like many others, I think a pump is great when everything is working well and am grateful to have one. Good luck.