I have a couple of questions regarding insulin lifespan. My doctor told me that once opened, insulin lasts the same amount of time at room temp as it does in the fridge. She also said that the max amount of time insulin lasts is 40 days, so I should throw out any insulin that old and start a new bottle.
Is it really true that, once opened, insulin degrades at the same rate at room temp vs. the fridge? This seems to violate laws of chemistry, but maybe someone can answer this question who has better knowledge than my non-expert surmising? And if the degredations rates are the same, why is that?
What are othersâ experiences with how long insulin lasts? Iâve marked when I start a new bottle (I use Lantus and Humalog), and they never seem to lose potency for as long as it takes me to finish a whole vial, about 2.5 months. To see if this is merely me not noticing a gradual decrease in potency, Iâve paid attention to when I open a new vial to see how potent it seems in comparison, and no, there doesnât seem to be any difference (i.e. no sudden increase in potency relative to my âoldâ vials). I hate to waste money as well as stuff that seems perfectly fine. Othersâ thoughts/experiences?..
I use mine past the 2 weeks that the manufacturer states, but I use enough insulin that a bottle wonât last me more than 3 weeks.
And yes it doesnât need to refrigerated as long as it doesnât get too warm.
Insulin is a protein chain. So itâs biologic and will eventually degrade. There is a preservative in it.
I think there are so many variables that the medical industry has to take, as a rule, the most aggressive approach. What is room temperature? Your room can be climate controlled but if your insulin is on a table and frequently gets hit by direct sunlight, you can cook it to a shortened life span rather rapidly. Is your room not climate controlled and you live in a hot vs cold climate? The only way to really find out is not to ask your medical professional but run your own test. After you have kept using your insulin for a few months, if your I:C ratio remains pretty much the same then you are fine. If your I:C varies just a little as every extra week goes by, you can most likely compensate but by testing you will know when enough is enough and the remaining amount needs to be discarded.
This is actually quite easy to test if you are on a CGM but even with finger sticks is not a difficult exercise.
I keep mine cool, and use a vial in about 9 days. If I take it out of the fridge for even a few hours I toss it rather than restore it. I usually say 24 hours out, it does not get put back. No evidence, just my habit. Even if it is not opened, it never goes back in if it has been outside the fridge for longer than 24 hours.
I never had any problem with Lantus not lasting. I have had problems with both Novolog and Tresiba. I believe that most insulins once opened are supposed to last 28 days, although Tresiba is supposed to last 8 weeks.
I find it a bit difficult to tell if an insulin has lost potency because there are so many reasons glucose readings can be off.
I never refrigerate insulin once it is opened, but make sure that it is kept either in a drawer that doesnât get too warm or in my purse.
In my 62 years of using insulin, I have had trouble with insulin not lasting maybe a total of 5 times.
My in-use vial is ALWAYS at room temp and lasts me about 3 weeks. My next-to-be-used vial is also at room temp because I keep it in my travel toiletries kit. That way I always have a full bottle plus whatever remains in my in-use vial if I hit the road in a hurry. So my insulin (now Humalog, but years of Novolog before that) ALWAYS spends 6-ish weeks at RT ⌠3 weeks in use and 3 weeks with the cap still on. Iâve never felt this has been problematic for me.
@BKN480 , your questions are valid. Remembering this is a support group, lets look at them.
After opening a sterile container and puncturing the rubber cap, there can be surface contaminates pushed into the insulin. Preservatives only fight so long in the effort to stabilize insulin and keep it wholesome. All of the various parameters are tested and applicable standards applied by the manufacturer when their application is submitted to the FDA for approval. 40 days is an agreed upon period of time arrived at by the manufacturer using a poly-factorial process and agreed to by the FDAâs approval process. âYour milage may varyâ is an old catchall expression applies here.
As I understand the guidelines in this group, it is a âsupportâ site. We are to support one another in our journey thru our personal battles with this crazy disease. That being said, my interpretation of those âsupportâ guidelines really mean if it is a âregulatedâ issue, all of the comments should point basic and advanced users to safe, well founded, and sound actions.
If someone were to say, âInsulin under refrigeration in a drawer with an ultraviolet-C, 50 lumen light has been used for up to a year after opening, as long as before the expiry date.â would not be providing sound supportive help
BOTTOM LINE: There may be many of us who in our own homes and just placing risk upon ourselves, get much more out of a vial of insulin. Many of us wish a vial would last 40, yet, instead us the 1000 units in less than 10 days.
JOURNAL ARTICLE: There is a published study out of refugee camps in Africa related to heat and insulin. It is the closest I have found. Here is the link:
I used to refrigerate, but for the last 30 years I just keep my insulin vials in the medicine cabinet. When a vial is nearly empty, I put it on a different shelf and those can get old. I live in earthquake country, and if there were a time when I could not get refills for awhile, I at least have some small quantities left over. Better than nothing. I have had occasion when my pharmacy took too long to refill, I ran out and actually used the old insulin. I tried to compensate for the reduced-potency, and since I use a CGM, I know pretty quickly if I did not compensate accurately. Bottom line, I am completely comfortable using quite old opened insuin as long as I adjust.
I would recommend new T1Ds follow the guidelines, but as your self-care skills and experience increase, it may be possible to relax a bit and still be safe. The guidelines are there for a reason â safety â and both the manufacturer and the FDA in the US will lean towards being conservative. So if you avoid the obvious like ultra-violet or sunshine and heat, you likely can be quite safe when using opened insulin after the recommended time period. But know what you are doing and really keep track of your BG levels.
Iâve been using Fiasp insulin penâs for about 3 years. Normally I have a pen room temperature 20-30 days never had any trouble. I do try not to let them get warm (donât leave them in the car).
You have done the experiments, and you see the results. I could think up excuses to justify your doctorâs position, but why should I? For strange reasons I have spent a significant part of the last few years evaluating research projects, mostly in the life sciences, and I have developed a philosophy which says Donât argue against the facts, unless youâe got a really good reason.
If itâs convenient, do the experiments again at 60 days, 75, whatever you like. To repeat a warning I saw a long time ago, donât assume the the dropoff in potency (or any other function) will follow a Gaussian curve. Potency might jump up in an enormous spike at 53.2 days, and then drop off a cliff. Until the next bottle does the opposite.
A few years ago, I asked my doctor if I really have to half-sterilize the injection spot with alcohol before I inject. He shrugged his shoulders and said stop cleaning the spots and find out. Iâm on MDI, havenât cleaned an injection spot in several years, and Iâm still around to talk about it.
To get back to the point, I have often used Novorapid which has been at room temperature, used, for many months, and occasionally used Toujeo which has been more than a month at room temperature after being used, and have seen no difference in their potency.
I have been using insulin pens for over 20 years, and typically keep unopened pens in the refrigerator. That being said, a box of 5 Humalog pens lasts 3 months at my current dosage, and I typically receive 2 boxes at a time. I have never experienced a loss of efficacy even for pens I have stored for up to 180 days.
The pens Iâve disassembled are plastic on the outside mechanism, but the insulin itself is in glass tube encased in the outer plastic.
Both pens and vials have rubber stopper on one end. Now there is a rubber/plastic plunger âpushingâ on the top end of a pen.
I should disassemble a pen and post pictures of the innard la here. I always end up breaking the inner glass vial but maybe I could use a cutter on the plastic instead of brute force. The neatest thing is the long spiral scale.
When I received my pump last year, I had almost a full complement of pens on hand. I figured out how to remove the glass vial from the pens and used that insulin for several months.
The trick I used was to take a pocket knife and very carefully slide it up under the top of the pen starting where the protective plastic covers the vial. This is not where the glass is exposed but where the upper plastic meets the plastic protecting the glass vial. Once the knife was up under the upper part of the pen, Iâd turn the knife and lift up until the outer plastic broke. Then the two halves would pull apart and the glass vial would slide out of the protective lower half.
I no longer have any pens so I can not demonstrate how I did this.
