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Insulin pen too hot?

J

jalu47

Member
Messages
15
Type of diabetes
Type 3c
Treatment type
Insulin
My rapid insulin has had really poor effectiveness today, after an hour 2 units dropped my blood glucose by 0.1.. I’m worried the heat has affected my pen.

Still a newbie so not really sure?

To note I am on steroids at the moments following a chemo dose but other similar days have had much better results.
 
Heat does effect insulin, if in doubt change the pen it's essential.

Never leave insulin in a hot car or in the Sun as does freezing it both destroy the insulin.

Kind regards Martin
 
I’ve been quite careful to keep them out of direct sunlight / car and always in a case within a bag but it’s been so hot I just wondered if it could be that.

Is it worth putting back in and out of fridge at home even when in use? Wasn’t sure if that would be worse to go up and down in temperature?
 
jalu47 said:
I’ve been quite careful to keep them out of direct sunlight / car and always in a case within a bag but it’s been so hot I just wondered if it could be that.

Is it worth putting back in and out of fridge at home even when in use? Wasn’t sure if that would be worse to go up and down in temperature?
Click to expand...

Don’t put a pen back in the fridge once you’ve started using it, this is against manufacturers advise as per the leaflet - I think the big change in temperature from warm room to cold fridge will negatively effect the insulin - so it won’t work the same
 
Chrissy8 said:
Don’t put a pen back in the fridge once you’ve started using it, this is against manufacturers advise as per the leaflet - I think the big change in temperature from warm room to cold fridge will negatively effect the insulin - so it won’t work the same
Click to expand...
It is against the advice, though the advice on my Novorapid leaflet has no particular emphasis on this point (IMO - your opinion may differ from mine), so I assume it's simply down to a lack of testing rather than that the insulin will change in any way. I quote: "Novorapid(R) Penfill(R) that is being used or carried as a spare is not to be kept in the refrigerator. You can carry it with you and keep it at room temperature (below 30degC) for up to 4 weeks."

Certainly when abroad somewhere hot I will put my pens back into a fridge (if available) rather than risking them getting hot in a room without my realising, I also have no problem injecting from a new vial that's just come out of the fridge (though it feels a bit odd :)).

You have to interpret the rules as you see fit, I'd be interested to know if there is some sort of scientific basis for not placing in-use insulin back in the fridge though.
 
I keep insulin in the fridge until use and then in a Frio bag once I start to use it. Got the Frio bag after I had some insulin overheated during the hot weather last year (I was ill for a couple of days as a result - because think it affected both my basal and bolus insulin). I use the Frio bag all the time now so there is no doubt about whether the insulin has been overheated (I just find the inner bag does not need soaking as often in colder weather).

Ed: I think you tend to get air bubbles in an insulin pen if you put it back in the fridge after use ... and I found it stings a bit when injected so just use the Frio bag ... ymmv
 
Thanks all for your advice… I’ve had a much better day today so think there must be other variables at play. I’ve got a cool pack for my insulin case which I may start to use in this weather!
 
I thought the advice against storing insulin in the fridge is that it can result in micro bubbles when injected too cold and should be used at room temperature.
 
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