Do you keep your pens in the refrigerator after first use?


The instructions for all insulin pens say not to keep the pen in the refrigerator after first use of the pen. We are supposed to keep them cool/cold (but NOT frozen!) until first use in order to keep the insulin fresh. The directions are very clear however that once a needle has been placed on the pen and the first dose drawn the pen is not supposed to be kept in the refrigerator. Why is this? It seems to me that keeping the insulin cool in the refrigerator at any time would be preferential to not keeping it cool. I can’t imagine why that would be a bad thing. The alternative is to leave the pen laying about where it will cycle through daily temperature fluctuations or, even worse, carrying it in a purse or pack where it will be jiggled about and experience even greater temperature fluctuations. So why is it a bad thing to put the pen back in the refrigerator until its next use?

In my case I use only 10 units of Levemir in the morning. (I use another long lasting insulin for my night time bolus.) That means my Levemir pen sometimes lasts longer than the throw-away date after opening. This is even truer for the Symlin which I use even smaller doses of. I seldom toss them on those dates largely because I hate throwing away still-good product and that gets expensive. If I sense any degradation of performance I toss it immediately. Otherwise I push those throw away dates. Do you toss your pens away on such a schedule? I figure if I keep the pen in the refrigerator it is going to stay fresher through the end of the cartridge than not. But the instructions specifically warn against that. I appreciate the insulin companies want to error on the side of safety and fresh insulin so for them it makes sense to insist that a pen be tossed 30 days after opening. What do you think? TIA.

I can’t answer the question of why you shouldn’t refrigerate after opening, but I also practice the “if it ain’t broke don’t fix it” approach to insulin usage dates.

I would ask either someone from the company or a pharmacist. Problem is a company rep has guidelines that they have to follow so you probably won’t get anything else. They may be able to tell you why, though. I don’t see why you couldn’t return it to the frig after each dose and keep it fresh longer!? Maybe it has something to do with once the top is punctured it allows exposure to the air and that has an effect on its life?

You are correct. The companies keep their agents so tightly locked down they can’t say anything that’s not in their book. Hence its just more of the same. Likewise most pharmacists and pharmacy agents. I did ask a pharmacist once off-the-record and he couldn’t imagine why keeping it refrigerated would be a problem. He offered a guess it might have something to do with viscosity and the narrowness of the needle. But if the needle is fresh or the pen is allowed to warm up just a little he didn’t think that would be an issue.

And yes, once the top is punctured some air is likely introduced into the cartridge. But, unlike a vial, the cartridge volume shrinks with the plunger so even that is minimized. And one would think the cooler air would be less volatile and better than warmer air.

I just thought of something else. Back in the day when all we had were vials it was recommended we warm the insulin by rolling it between our palms in order to warm it up and make it more comfortable to inject. But we can’t do that with pens. Maybe this whole thing is just a comfort issue. Personally, I’ve never had a problem with injecting cold insulin. Maybe others have. Go figure.

For my novolog and symlin, I keep the pens in the fridge between use. I live in the desert and don’t want to take a chance on it getting warm. Who can afford to waste it.
On my lantus, I use opticlick, so the pen stays out and the cartridge stays in the fridge.

I think it says 28 days, not 30, and not because it goes bad but because it supposedly becomes contaminated by then. Does seem like a waste. Cold insulin is supposed to injure the tissue and cause pain. Has anyone experienced pain from cold Insulin?

I recieve my sons’ insulin via mail. It comes well protected, but during the summer months and if I am not home I have received it and the ice pack was melted and the insulin was not cold but not warm. I called my pharm. and talk to a to the actual pharmimist (sp) for a long time. He assured me it has high heat tolerance and it would have to sit out at hi temps for a long time (lantus) is what I was asking about. So sitting out and not being ref. is fine I believe. As for using past date, we use it up before the 29 or 30 days so I don’t need to worry. But I have to say I have good insurance so can’t comment, but like to follow directions. Its on my 11 year old son. If it were me I might feel different. Your the best judge if its working.

No After using my own for the first time I always leave it at room tempature. It will last 28 days at room tempature. Cold insulin is much more painful too inject! I’ve had no problems leaving my opened pen out of the fridge. I Always store my un opened pens in the fridge though.

I have at least six hundred units of novolog in the fridge has been there since the 28 days are up three pens. was scared to use any after the 28 days, I had a buddy who’s been dealing with the d since he was 4 and told me that expired insulin can make you crazy emotional, so hence my caution. stil the overall expiration isn’t till 2112, seems confusing ?

I was just put on insulin YESTERDAY (I guess my time of pills and diet only are gone!), and in reading all the documentation that came with my Lantus SoloStar said that if I put the pen in the fridge after first use, that taking it out and injecting it right away, would cause a burning sensation. So, I took my first pen out last night, and then used it this morning. Went in, slicker than a whistle, and I had NO pain during or after the injection.

All business manipulations by companies to keep rising their sales

from what I read, once a pen is opened, you have to toss it 10 days later.

I use mine till it's gone, regardless of the time frame. And once opened, I don't put it back into the fridge.

At nearly $300/box, it's like liquid gold.

Not sure about putting it back in the fridge once opened. I never have. This is my 3rd time using insulin in about 8 years. I need insulin during pregnancy. Although I did start lantus before I got pregnant this time. I use the pens well within the 28 day range as I am already on about 110 units of humalog daily and there’s only 300 units of it in the pen so mine never last nearly a month…I do remember using the viuals of insulin and I would use them until they were gone or they weren’t working anymore…