Insulin left outside in car

If I left my insulin in the car overnight and it hit 30 degrees out would it have frozen up in the car? If it wasn’t is it still good?

I would be very surprised if it was bad.


Is it gone cloudy instead of being clear ? Most insulin are clear except NPH.

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There’s no harm in trying it, so long as it looks normal and you’re careful. Insulin is surprisingly more durable than we think. Even if it has degraded a little bit, it may not be noticable.

I would take your next bolus with it (by syringe, not in a pump). You’ll have to closely monitor BG, though. If you see sugar rising more than you’d normally expect, then you’ll know it went bad after all. Correct with a different vial, if necessary. No problem to be had, unless you ignore possible rising BG.

Like El_Ver, I’d be really surprised if it were bad. Just because it was 30 outside, doesn’t even mean it was below freezing where you had it stashed.

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Probably not. The car insulates things. Did anything else in the car freeze (like did you have any half empty pop bottles rolling around in the passenger side that froze or didnt)? I vote for “Its OK,” at 30.

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Frozen insulin works great!

Well, once it is thawed.

I just tried it out.

There has been some discussion on this very topic on FUD lately. A very unscientific study that does suggest that once frozen, it is still safe to use, but has a longer action curve than normal. I personally would use it. Even if it is half as effective, that’s still $$ in my pocket.