I am using a vial of Humalog that I didn't actually "open" (puncture the rubber top with a needle) until July 24. I took it out of the fridge the night before (July 23), so I would normally discard this vial 30 days later (which would be August 22).
However, this vial traveled with me twice in July as a back-up vial. It was out of the fridge for 4 days at the start of the month plus 2 days later on. When I returned home, both times, I put it back in the fridge.
So, should this vial be discarded 30 days after I started using it? = August 22,
30 days after I started using it minus the 6 days it was at room temperature = August 16 OR
30 days after the first time it was out of the fridge: July 1 + 30 days = July 30
I would appreciate your opinion. I am going to be traveling next week, and don't want to be using insulin that's lost its potency.
Based on the information provided by the manufacturer, humalog kept at room temperature lasts 28 days, and going by the book, you should use it within 28 days of the first exposure. That would be the conservative answer.
However, heat damage tends to be cumulative and if you kept the pen in the fridge in the interim it would “probably” be good. You just need to make a decision based on how well you think you can detect it losing effectiveness, the difficulty in replacing it and how well you can refrigerate during your trip.
I think we can each vote. I vote for 30 days after using it minus the 6 days at room temp.
But, seriously, heat is damaging. I can’t predict when it will suddenly lose effectiveness. You have to use it and find out. But keep it cold between shots.
Personally, when I travel, the backup vials are laying with ice cubes around them, or blue ice around them. They never freeze, but they’re kept cold.
Since I do not otherwise remove vials from the frig, I do not adhere to any discard date. If I notice I’m using any more than usual, in the absence of other factors raising my BG, the vial gets tossed. My present vial will last me til mid-Sept.
If you are traveling with a vial that has been warm awhile, you’d best have another ready to use - but keep it COLD. Otherwise goodbye potency, hello hyperglycemia.
Do you know if it were me, I’d have probably discarded that vial and opened a new one in order to be sure of consistent action.
I say use it till it’s gone, and not to worry about how long it has been open. I have never seen a loss in effectiveness due to heat or length opened. I had an open bottle of Humalog in my car for over a year, and used it in an emergency situation. It still worked great. I have regularly had multiple bottles opened at a time for months and never had a problem.
Now I wouldn’t recommend doing this on a regular basis but now and again is no problem.
