Novolog Expiration? 28 days?

I just started Novolog. I keep a pen in my purse to take to work and when away and I keep a pen in the kitchen. Yesterday and today my bg was 290 fasting and 310 yesterday.

I think the pens are expired. ?? Is it 28 days outside refrigerator?

I also take Tresiba and know it lasts 6 weeks outside fridge.


Novolog is fine stored outside the refrigerator for 28 days. Usually the pens have an expiration listed on their barrel. The expiration corresponds how long it will be good stored in the fridge, usually more like 2 years.

Sometimes your blood sugar is whacky. Try to go to bed with a good blood sugar number and if you awake high then correct. And if it isn’t down to a good number in 3-4 hours then correct again.

Thanks I threw out the 2 Novolog pens this morning and will mark 28 days from today. Maybe just a whacky weekend for me. Thanks,

Were your pens exposed to overly warm conditions, e.g., by the floor heat vent in your car?

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Hi @Yoga62, we are somewhat novices at this (Dx early last year). We have suspected bad insulin a few times - but every time we found another reason in the end. Possibly you are coming down with something?

EDIT: Also - a lot of people on the forum have mentioned that insullin tends to remain good a lot longer than the official expiration date. FYI we keep using our pens through even after the 28 days are passed. We have not noticed less action or different carb/ correction ratios.

Tresiba is 8 weeks at a pretty liberal definition of room temperature (up to 86f). Novolog is 4 weeks at room temperature…

Many of us have pushed novolog a little beyond that without noticing any problems.

I used to always mark novolog pens on opening date with a sharpee then put a piece of scotch tape over it because ink will rub off… nowadays I pay less attention to expiration dates… but yes by the book it’s 28 days for novolog and 56 for tresiba

I routinely keep Novolog vials at room temperature for at least 6 weeks until they are empty. I’ve never noticed a problem. I’ve never used Tresiba.