28-Day Guideline for Insulin

I've been told by our ped endo that insulin is only viable for 28 days after opening the vial.  After the 28th day, we need to throw it out.  Do you all stick to this guideline?  Do you use the entire vial?  In your experience, is there any degeneration of the insulin's effectiveness after 28 days?  Or is this kind of like the cosmetic industry's admonition to throw away your mascara and buy a new one after so many months because it might "go bad"?

Replacement of insulin is not really an issue for us cost-wise, because our insurance covers it.  But, they will only allow one vial each 28 days, so we don't have a back-up on hand if something happens to the open vial (drop/break/loose/overheat/etc.).  Do you keep an "old" vial on hand for backup?  Or am I worrying about non-issues?



Hmmmmmmmmmmmmm good question.  I used to use my vials for longer than a month (when I was on limited amounts) but now I go through them pretty quick, Novorapid especially.  Try using pens?? if you son is on Lantus (not sure if he is) you get 5 pens of Lantus in a box and they usually last me a couple months!  It's good for a month after you use it for the first time.. so I go through one every couple of weeks .. X5!

Same with Novorapid, it comes with 5 penfills.

Just a suggestion.

I did notice when I was using vials that I would tend to throw more out because it didn't work as well.. but don't quote me on it because I've been on pens for a long while!

I agree.  I use Lantus pens and the box lasts me somewhere around 4 months usually? Give or take.  I do believe I've had bad experience with old insulin before.  When I used to just get vials, sometimes I would stretch them.  They seem to last a lot longer than a pen.  

There was one week of highs that I had when I was using insulin that was probably 7 weeks old.  My doctor stressed to me at the last visit to toss it after a month.  Like I said though, the pens don't usually last an entire month anyways, but I won't use old insulin again.

It's a great idea to get pens/cartridges instead of vials.  I don't use the pen much for my son, but I love the little vials that go in the pen because he doesn't use too much right now and we end up throwing a lot less away.  You can just draw insulin up into a syringe from the pen/cartridge.   It gives us a great backup supply.

Thanks for the feedback.  I'll look into the pen at our next appointment...



I know the pens are supposed to be thrown out every 30 days. Which is what I'm on. I actually had to throw one away today because I kind of started seeing my blood sugars getting higher. But if it seems to stay normal and it's been longer than the 28 days I say don't worry about it.

From what I've gathered from the doctors I've seen over the years there shouldn't be a problem.  I've been told the only time you should throw a bottle of insulin away is if your sugars go unexplainably high and you've tried everything else.  I've also heard that the expiration date on insulin isn't that important as long as you keep it cold and unopened.

I'm sure that the viles are a little better than the pens because the pens you don't normally put back in the fridge. So I'm assuming that they would last a little longer than the pens.

One of the ways to judge whether your insulin is still good is to check and see if it is still absolutely crystal clear.  Almost all doctors recommend that if the insulin is the slightest bit cloudy, throw it out.  They also recommend not using the little bit of insulin which remaim in the skinny neck of the bottle.  You can always compare the clarity of the bottle you're resently using with an unopened one.  Reusing syringes is another thing which will cloud up insulin and decrease its life.  This is because the tiny bit of insulin which remaims in the needle of the syringe will usually crystallize.  When you re-insert the same syringe back into the bottle and inject air some of these crystals might enter the bottle.  They will act as a "seed" for growing larger crystals within the bottle.  Reusing syringes is not advise unless you have to for financial reasons.  Both insulin which has been exposed to extream heat (like in the glove compartment of a car) or was frozen )not just cold but actually frozen) should be discarded immediately.  Using the same syringe to take different kinds of insulin (such as Lantus and Humalog) is also not advisable.  You can end up with one kind of insulin whose duration properties are unknown.


One other thing I do for the "in case of emergency" bit is ask my doctor to put in a prescription for 1 vial of a competing brand of fast acting refillable 3 times.  In my case, Humalog and Novalog work identically so they are an easy swap in an emergency.  My insurance won't cover an early refill of humalog but if I go to the pharmacy and pick up one of the 3- it's a whole new prescription, drug, etc.. Silly, but it works.  The other thing to remember is that in most places (I think) Regular insulin is not a prescription item. It is slower and a little more annoying to figure out timing for but in a pinch you can always run up to the pharmacy and buy a bottle.

We with tile on our kitchen floor have definitely had insulin emergencies at odd hours…




Since "need insulin to live" is in all our vocabulary - it is NOT a non-issue!

I don't go by it.  I use every last drop in the vial.  A vial of Humalog last me about 35 days and Lantus about 50.  So I don't sweat it.  I've never had any problems with this that I know of.

I was told insulin is good for one month after opening it, but to throw it away after that because it isn't as affective as it gets older.


DDrumminMan: if you don't use yours all up in a month, that's simply a sign you need to eat more food lol!


But when I was on shots, I did keep extras in the back of the fridge in case I ran out or had a clutz moment and dropped one.... hey, do those break when you drop them? Very easily, I mean :) Just curious.

[quote user="A-D"]

We with tile on our kitchen floor have definitely had insulin emergencies at odd hours…




Holy s**t, it just happened!  Hubby opened up the fridge door, our ONLY vial of Lantus came flying out and shattered into a billion tiny pieces on the tile floor!  I'd be crying, if I weren't laughing so bloody hard!  Thank goodness we already gave William his evening dose.  So, I'll be off first thing tomorrow to the pharmacy to negotiate another vial of Lantus (pretty sure we're covered by whatever bewildering calculation the insurance company does for doling out insulin).  Already explained to My Dearest Love that we keep with insulin in the butter nook WITH THE DOOR CLOSED so it's safe and sound.  Apparently he forgot the "closing the door" part when he put it away.  That'll teach me to leave him in charge for 5 hours while I run off to diabetes class :)

Mo - still giggling hysterically....


Wal-Mart sells Novolin-R, Novolin-N and Novolin 70/30 under their own brand name "ReliOn" for around $23 per bottle.  None of these requires a prescription and Wal-Mart stores in most areas are open very long hours, seven days a week.  Wal-Mart saved my life on a few occasions, including one which lasted almost four months when I was unfortunately without health insurance.  They also have had some very good deals on glucose meters and test strips.


If I've said it once, I've said it a thousand times...  There are very few new mistakes left... I've made most of 'em more than once, LOL

I trust all will work out for you!



(having had to revert back to NPH and Regular in one tight spot because I couldn't get the over-sunned insulin I had carried with me "for safety"... replaced LOL)