Spoiled insulin

[ce81ar]

This last summer with the higher temperatures I really struggled with persistent high blood sugars and eventually managed to narrow it down to the insulin itself (Novorapid) not working well. I changed from having my insulin delivered by post in a chilled pack, back to my local pharmacy because I wasn't convinced it was staying properly cold en route to me. This solved a lot of the issue but I was still getting occasions towards the end of a reservoir where I started to need 10-20% extra to keep under control. As the temperatures dropped, everything started to work better.
Then I went to work in Qatar for 7 weeks. Given my prior experience I bought some frio packs and transported my insulin out in those and then stored it in the fridge in my hotel room. Whilst not always at 5oC, the fridge was keeping everything much cooler than the room ambient of 23C (I recorded the occasional spike to 15C after putting things in and out). Everything went well for the first 3-4 weeks and then I started to find my blood sugars were creeping up. Temps over there in the autumn are similar to a UK summer, so it wasn't crazy hot, and at no point was the insulin above the recommended temperature(30C max). The last 2 weeks have been a real struggle and I flew home with double bolus for each meal and 130% basal. Changed immediately to a new vial kept at home and all went back to normal.
Has anyone else had any similar experiences? It seems that the official temperature ranges suggested for Novorapid are not actually correct and I'm having major issues at much lower temperatures. I'm due to go back out for 8 weeks in January so need to find a workable solution.

 

[kitedoc]

Hi @ce81ar, from my experience as a T1D, not professional advice or opinion: I am assuming you are using an insulin pump.
As you may know, the blurb on the pamphlet accompanying your Novorapid states that it has to be kept between (about 2) and 8 degrees C for long term storage. And is inactivated by being frozen.
And that out of the fridge it lasts about 28 to 30 days if kept under 30 degrees C.
If you cannot be certain that the Novorapid was kept between say 2 and 8 degrees C during air transport, and if the fridge you were using in Qatar was not keeping it within the required storage temperature it is possible that after the 3 to 4 week mark the remaining Novorapid might have lost its efficacy. Or perhaps in addition, if you were carrying a spare ampoule or several sequentially over the time of Novorapid with you it/those may have been exposed to temps > 30 degrees C.
For future it may be safer to actually plan to have Novorapid dispensed after say 3 weeks at your working destination.
And I am assuming that there were no cannula bending or leaking cannula episodes that added to or caused some of your troubles??
With my new Tandem Slim pump (one of the replacement options in Australia for the Animas pumps) there is an alarm for the insulin cartridge getting too near 30 degrees C (or zero degrees C) and another for the pump machinery temp reaching critical levels ( of course not nuclear explosion but breakdown of the electrics)!!
In Oz I have sometimes carried my pump wrapped in a towel with an ice pack in 40 degree C heat, as well as having spare insulin in the car in a insulated bag with ice packs, a thermometer and cool drinks)!!

 

[jrussell88]

I spend long periods when my insulin is often around 35+°C during the day and haven't noticed any degradation for the three weeks the insulin is at these temperatures.

I keep fresh insulin in the fridge, but don't bother to refrigerate when I'm travelling as I've never experienced any degradation.

However I would be careful not to leave it in the sun or a hot car.

 

[kitedoc]

I spend long periods when my insulin is often around 35+°C during the day and haven't noticed any degradation for the three weeks the insulin is at these temperatures.

I keep fresh insulin in the fridge, but don't bother to refrigerate when I'm travelling as I've never experienced any degradation.

However I would be careful not to leave it in the sun or a hot car.

With respect @jrussell88, What is important is the temperature of the insulin itself in an ambient temperature of 35 + degrees C.
As you say you do not expose your insulin into situations where the ambient temperatures could be even higher.
Have you thought about having a thermometer next to your insulin and checking periodically what that reading is?