Different Results with Different Brands of Metform

Hey guys,

Question: Has anyone noticed one brand of generic Metformin being less effective than another brand?

For the last 2 months, my blood sugar has been running about 30 points higher than usual with some spiky behavior I had not previously seen. I use a Free Style Libre and have had predictable readings for a few years. This is definitely out of the norm.

Took action to further reduce carbs & calories, lost 4 pounds, and no improvement. Changed sensor and no improvement. It certainly possible that this is age-related, but seems very sudden.

Last night I realized that my pharmacist filled my last Metformin prescription (short-acting) with a different brand about 2 MONTHS AGO. The new manufacturer is Asceno. At the time, I noticed the different tablet shape and also that this version has the unfortunate “fishy” order. So . . .

Could Asceno Metformin not be working as well as my previous brand? Is this possible? Has anyone heard of such a thing? I plan to talk with the pharmacist on Tuesday, but would love to hear from you guys if there is any wisdom out there. I will probably insist on swapping for a different brand just to see what happens.

Thanks so much!


I would definitely get the pharmacist to fill you a prescription with the original Metformin and give it a month. Be aware that it may be your Beta cells are tiring, no longer able to secrete enough insulin.

I’m not saying this is true for you, just going on my own experience. After several years on Metformin, with no changes in diet or exercise, my BG started to increase. Like you I decreased carbs and increased exercise, but the numbers continued to climb.

For me the next step was to add 1 injection daily of long insulin. It was at this time that my doctor informed me of the possible progression of type 2 DM.

That’s one of the reasons I believe in self testing, regular labs and doctor visits.


Do you know if they are the extended version, or could that be a difference?


I just did a search on Asceno Metformin. It came up Ascend Metformin and it appears this is extended release. If your original Metformin was regular, that may be the difference.