Insulin frequently going bad after only 1.5-2 days

My Novolog insulin in my Medtronic pump keeps going bad after only 1.5-2 days. Suddenly, the BG's start shooting up really fast on my CGM and sure enough are confirmed by my Meter. I first try to determine if the fault is from carbs, insertion site, bubbles in tubing, etc. Finally I change the insulin and then finally start seeing the numbers go down, but I have to be so careful and wait, since I'm not sure what of any old insulin might still be functioning over the next 4 hours before I can correct the highs completely. It has kept me up several different nights now when it has happened, since I feel I have to keep watch and make sure. I used to be able to have the insulin last 3-4 days in pump, even in summer like now. What is going on? Someone once gave the idea that mail order pharmacies do not keep their insulin shipments cool enough in transit and that causes them to go bad faster, hence we should buy our insulin direct from pharmacies. Can anyone speak to that? I have had 2 different mail order pharmacies and they both have caused this, I'd have to say. I asked the local pharmacy once about getting my insulin there, and the cost was a lot higher that way, even under my insurance. But if that gives me more reliable lasting insulin, that might be worth it. Thoughts? (BTW, I did try searching for this topic on this site but either I can't search very well, or it hasn't been discussed.)

Have you tried to change the reservoir? If you insulin polymerized in the reservoir then it would lose effectiveness and worse, new new insulin added to the reservoir would be contaminated and also lose effectiveness. It is like a chain reaction.

Hi, Brian. Thanks for replying. Yes, absolutely, I changed the whole set with the new insulin, once I saw all the other factors were not the cause. Changing the whole insulin set is always the last resort and it does get results. But that wasn't really what I meant in my question. I would like to know what the problem could be that my insulin keeps going bad after only 1 day or so, when I used to get 3-4 days out of a reservoir. (My insulin dosage is very low.) I have tried different mail order companies and different batches and different bottles, but I continue to see the insulin go bad after 1-2 days pretty frequently.

What about the heat? Do you wear it outside working or playing in the sun or heat? I know that mine starts losing effectiveness if I've been outside a lot for a couple of days and then I just change the whole set up.
When I was traveling out west to AZ I was smart enough to make sure my pump stayed cool but it took me a while to realize that while I was just at home doing my everyday thing that I had to pay attention to that heat exposure.

Ok, I just know that some people refill their reservoirs even though that is not recommended.

Insulin can lose effectiveness for a number of reasons. As PedsRN mentioned, heat damages insulin and you are supposed to keep insulin (in vials) below 86 degF. For pump use, insulin's (like Humalog) are supposed to be good for up to 7 days as long as you don't exceed 98.6 degF. But the manufacturers throw up their hands with higher temperatures, for instance Humalog's prescribing information says:

Insulin exposed to temperatures higher than 98.6°F (37°C) should be discarded. The temperature of the insulin may exceed ambient temperature when the pump housing, cover, tubing or sport case is exposed to sunlight or radiant heat.

Even though the pump is next to your body, if it is hot out or in direct sunlight, that can cause problems. And if you overheat at night in bed, that can also be a problem.

ps. Exposure to light can also be a problem, if you leave your vial out in the light, it can degrade just from the light.

Yes, I know about the heat, but maybe I’ve just been lucky up to this point, not having that much of a problem with the insulin going bad from heat exposure so quickly. My Dad lived in AZ and even there, it never was a problem for me (of course, in A/C most the time.) HOWEVER, I AM in menopause and have the sweats and hot flashes through the night, so even though I’ve had those for over a year now, maybe those are indeed adding to the decline of the insulin since those sweats get awfully hot and I usually keep the pump attached to my waist while I sleep. Aha! I think I will start resting my pump far away from me, outside the sheets, and see if that helps any. Thanks again for the thoughtful replies and concern. It means a lot.

Something that I do is always keep the vials regridgerated-even after I start using one. I fill the reservoir, then put in right back in the fridge until 3-4 days later. I always noticed that this results in less air bubbles when filling the reservoir too or air bubbles that are easier to get rid of.

Since you change the insulin and the site at the same time, perhaps you are experiencing site absorption problems. It's interesting that you consistently observe BG hypers between 1.5 to 2 days, a relatively narrow window of time. To rule out poor site absorption as the root of this problem you could do two things: use a site that you've know you've never used before and/or switch to a different brand of rapid acting insulin.

When you switch sites, do you notice any redness, soreness, or swelling at the site? I only mention this because I had a localized allergy reaction to Novolog. It seems that there's a lot we don't know about the site kinetics of a sub-q insulin infusion site. I speculate that a PWD's immune system may start to "defend" against the cannula and the forming insulin pool. More knowledge in this area could be very useful to pump users.

By the way, I get my insulin from a mail-order firm and they always overnight ship with cold gel-packs. The packs are cool when I get them. I like this as it confirms to me, at least for the shipment duration, the insulin has not been heat-damaged.

Good luck with your troubleshooting. Please post an update if you identify the root cause.

I have had a similar issue and was told to chnage the infusion site evry 2 days, The reason given is that the immune system is blocking off the cannula very rapidly (this is the sign of a strong immune reaction). Doing this has solved it for me for the moment

Susan - I had another idea but it's just a random guess. Please excuse my direct question as it's indelicate to inquire about a woman's weight. Have you experienced any slow weight gains, perhaps spread out over several years? Has your total daily dose of insulin trended up over many years?

The reason I ask is because I am a slow onset T1 (T1.5) and I became insulin resistant. I had no idea that a T1 could experience this. Once I changed my diet, lost weight, and reduced my insulin use, more normal insulin action returned. Just a thought.

HI Susan, I have had the exact same thing happen twice this summer. I use an Omnipod pump. The first time I was using Apidra the second time I was using Novolog and both times I had the pod located on my arm. Both times I played golf and spent more than 5 hours in the direct heat of the sun. Since I am very new to a pump (5/26/13) I was shocked my blood sugar could rise that fast 131-353 in the space of an hour. And 116 - 373 in the space of 2 hours. I went on the insulin manufacturers' websites to check the storage conditions for various insulins. Apidra seems to be the most temperature sensitive and Sanofi recommends discarding any insulin in reservoirs or pumps after 48 hours. Humalog and Novolog both are supposed to be less temperature sensitive and according to Novo their insulin is good up to 6 days in a pump. Since I throw out the pod after 3 days it is not a big concern for me.
I also get my insulin via mail order and it is always packed in thermal coolers with plenty of ice packs, and is sent overnight. You might want to check with your mail order company and make sure they ship it properly. It might cost you a little more to have it shipped express but it's probably worth it in the long run.
Because the pod is directly adhered to my skin it made perfect sense that the insulin had gone bad while I was out in the sun. It had gotten super heated. It is entirely possible that could be happening while you sleep ? I have not quite reached menopause but I am dreading it.
The first time it happened I freaked out took a big correction dose of apidra with a pen and of course suffered the hypo from over correcting. I changed out the pod and within a few hours my blood sugars started to return to normal. I saw my endo a few days later and got a sample of novolog to get started with and have been using that ever since. The second time it happened this time with novolog, I already knew the drill and swapped out the pod pretty quickly so I didn't spend hours with hyperglycemia. But over heated insulin was the root cause each time.

My pods last only 36 hrs if lucky
Sometimes hours before Insulin acts compromised , and a red blotch appears at the cannula site when I remove the pod showing that it was time to change because of this.
During global warming summers if I don’t stay in air-conditioning the pod has a potential of frying the insulin and sugars sore to 300 in no time , physical exertion in warmer weather also compromises my insulin in the pod many times. My skin temps feels at certain times way above what the insulin can handle in the reservoir of the pod. Does anyone else experience these symptoms?

Does that red blotch also show inflammation as in a raised round bump? I had to abandon Novolog (Novorapid) insulin due to this allergic reaction. It created poor absorption as I watched glucose levels rise to the 200-300 (11-17) levels. In my case, it was not ambient heat but an infusion site allergic reaction that destroyed my glucose control.

The reason I mention this is that I’ve been wearing pumps since the 1980s and I’ve never had pump insulin go bad due to local temperatures. I don’t live in a tropical climate but have visited the tropics many times for lengthy stays and have also spent long days outdoors enjoying cycling when it’s hot.

I also had to stop using the Omnipod system after five months due to many kinked cannulas and occlusion alarms. People are generally happy with the performance of the Omnipods but there are a slice of users like me who don’t enjoy long-term success and move on to other equipment/tactics.

I live I. Los Angeles and on those 110 degree days.
And this year we had a 120, my insulin will stop working in a day.
During heat waves I fill cartridges for a day. But I keep the same Infusion set for 3 days.
It was easy on Medtronic. Still doable on tandem but I don’t have a lot is spares.

Terry under certain conditions especially with global warming I feel my skin temperature feels way hotter than it should be putting the pod through its paces , also I’m using
Humalog insulin as opposed to NovoLog.

My experience does not include 110-120 degrees. That is a challenge for an insulin pump. Maybe that’s a situation for using multiple daily injections as an emergency measure.

I think it’s the tubing where the insulin bakes. No so much the pump but they gets hot too.
I really don’t want to go back to injections. But ya know if I had to I would.

SusanT - Could it be that your last shipment of insulin wasn’t handled correctly? You mentioned that it just started happening, so I’m wondering if the entire batch that was shipped to you was, perhaps, exposed to heat in the shipping? Have you changed the bottle of insulin you’re using and is it still happening?

I get my insulin via mail order, too, but it always comes in a styrofoam box and, from May to September, they also ship it with ice packs in the box, so I’ve never had a shipment go bad, luckily.