Insulin pen markings puzzle

[Finwiz]

I use Trurapi and Abasaglar pens.

Trurapi shows on the pen "100 units/ml. I take 2 x 6 (plus 2 x2 for "test"). So per day it is 16 units. I would expect the pen to last only 6 days (100/16) but I get a lot more days. Am I counting this wrong?

Similarly Abasaglar has 100 units/ml. I take 22 + 2 test units per day. If I go by 100 units, the penshould only last 4 days.

The boxs have "5 pens of 3ml" as well. So, do each pen have 300 (3 x 100) units? This would make sense.

 

[Robin]

I use Trurapi and Abasaglar pens.

Trurapi shows on the pen "100 units/ml. I take 2 x 6 (plus 2 x2 for "test"). So per day it is 16 units. I would expect the pen to last only 6 days (100/16) but I get a lot more days. Am I counting this wrong?

Similarly Abasaglar has 100 units/ml. I take 22 + 2 test units per day. If I go by 100 units, the penshould only last 4 days.

The boxs have "5 pens of 3ml" as well. So, do each pen have 300 (3 x 100) units? This would make sense.

Yes, each pen contains 300 units, or 3ml.
( They have to put the '100units/ml' on the cartridge or pen to distinguish them from high strength concentrated insulins, where you can get 200 or even 400 units per ml.)

 

[rebrascora]

The concentration of insulin is 100units per ml but each pen contains 3mls, so 300units each pen.

Just to clarify, there are different strengths of insulin, so you can also get 200units per ml and 300units per ml which are obviously stronger for people who need larger doses, so a 200units per ml pen containing 3mls of that concentration insulin would contain 600units etc.

 

[rebrascora]

Slow as ever and @Robin beat me to it. 🙄

 

[Finwiz]

Thanks guys. Perfectly clear now!

 

[Bruce Stephens]

Just to clarify, there are different strengths of insulin, so you can also get 200units per ml and 300units per ml which are obviously stronger for people who need larger doses, so a 200units per ml pen containing 3mls of that concentration insulin would contain 600units etc.

I think they come in special disposable pens, though, so you can always dial up the number of units you want and it'll work.

(Not like it was, pre-U100. Then we could get various strengths, sometimes different depending on what the pharmacist happened to have. (Though normally we got the same strength each time.) So (sometimes) we needed to inject different amounts to get the same number of units. Substituting different strengths was used a few times in crime novels, and I'm sure it lead to accidents. Thank goodness we have U100, so that's one category of errors that are pretty much impossible to make.)