Mixing Humalog and Novolog

My insurance recently made me switch from Humalog to Novolog, I’m on the T:slim pump. I’m on my last vial of Humalog but noticed that next cartridge fill will likely need to be topped off with the new Novolog vial. Any issues with using 2 different brands? I’m thinking not but wanted to be sure. Thanks.

Hi @DFBB the manufacturer says not to. While they work the same for me, I don’t know if I would mix them up in the same cartridge. Good luck!

I ditto Joe. Do you have any backup pens you could use to top off? If not, you might just need to lose a day on your cartridge.

Thank you so much for the help.

Diane @DFBB, I wouldn’t take the risk.

Although Novolog and Humalog produce almost equivalent results fo most people [I required slightly less insulin volume of Novolog], the two formulations are very different and mixing them could produce unwanted results. NovoLog is derived from yeast - brewer’s yeast - and Humalog is derived from a killed virus.

No doctor said there is very little difference when I had to switch way back. I would not worry about it at all.

I’ve used Humalog, Novolog and Admelog (depending on the whims off my insurance company at any given time) with no problem - but never mixed them. Since they are derived from different sources.L problems might result from mixing them together.
@808IUFan to clarify, did you mix the two types together, or are you referring to your doctor switching you from one to another?

When I ran out of one and moved to the other, they were mixed. I top off a pump reservoir because of the way my pump works.

Thanks for the help, my insurance made me switch from Humalog to Novolog and I’m on my last vial of Humalog and didn’t want to waste any of next tine I have a cartridge fill, so I wondered if I could use both to fill the cartridge, but I’m thinking after reading everyone’s responses that I’ll just use up whatever is left of Humalog and start fresh with Novolog next fill.

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It sounds like you may just have to change your cartridge a little sooner since you’ll be a little short. If you have backup Humalog pens you could top off using ones of them.

Did you ask the pharmacist? And your doctor??

Thanks for all of the suggestions, I did email my endo to see what she thinks.