I don’t use a lot of insulin, so each pen lasts a long time adter they are open, often more than 28 days…and my daily life takes me through frequent temperature variations of 100 degrees F or more. Therefore the best idea I’ve come up with, contrary to the manufacturers instructions, are to keep my insulin pens in the fridge even after they are open. My theory being that keepin them cooler would extend their effectiveness beyond 28 days, and that the relatively stable temperature in the fridge has to be better for them than the wildly fluctuating temperatures they would otherwise go through. So far this strategy seems I work just fine. Why do the manufacturers all specifically say not to refrigerate pens after their first use?
Sorry about all the typos-- (not so) smart phone
Ouch! My comment is that when I have injected with insulin straight from the fridge (which has been only a couple of times!) is that I noticed more pain in injecting (and experienced an extra nasty bruise one of the times)! I wonder if I'm alone in this experience or if this is part of what's behind the manufacturers' recommendations...
Hi Sam, what kind of insulins do you use? I find that Apidra is somewhat temperature sensitive, so I have to wonder if the kind of insulin makes a difference in whether or not to refrigerate.
I also wonder why one should refrigerate vials and not pens--maybe since the advertising talks about pens being so easy to carry around, they don't want to suggest refrigeration? Well, I do follow the rules, refrigerating vials and not pens...
Before I started pumping I always kept my insulin in the fridge, I would keep my open basal pin in a glass on the fridge door and would just drop my used pin needles in the glass so I always could tell if I had taken my morning and evening dose and every Sunday night I would trash them and start over. I also kept a novolog pin in the fridge and a second one in my small office fridge, also did the same thing when I was using the bottles and syringes.
I have never payed much attention to the 28 day rule, I don't even remember reading the white paper in the box for the first 10 or so years. I don't even remember the old stuff coming with a instruction sheet.
Yes, it is strange because Humalog says it's okay to refrigerate a vial after opening, but not the pen. Maybe it has something to do with how the needles fit or the measurement/delivery amount of cold insulin v. warm, growth of bacteria, etc, etc.
When I used a pen, I always kept it refrigerated after opening, but the ones at work stayed at room temperature. I never noticed any practical difference and I routinely had no problems using a pen older than 28 days, but within the stamped expiration date.
FWIW, on my pump, I always exceed the 7 day limit and again, there is no evidence that my results are worse as I go beyond 7.
Overall, I think they are just being cautious. YDMV!
I keep all unopened pens in the fridge and all pens with me in my frio. Sometimes if I'm too busy I leave the frio a while before I rejuve it. I have noticed that since I started using the frio I haven't thrown out any pens. I think the insulin lasts a lot longer than they say it will, depending on which one it is etc. Also a lot of my insulin was at too cold temps and it seems perfectly fine. I think we can just do whatever works best for us.