I was type 1 for about 50 years when I changed from animal insulins to modern day insulins. That led to my gaining weight and becoming insulin resistant (IR). I had to use a type 2 med to handle the IR. Avandia was the med my doctor chose, and I used it successfully for 12 years, starting in 1999. Avandia was found to cause many users to have heart problems, so my endo would not renew my prescription, and he prescribed Metformin in early 2011.
I have mixed emotions about Metformin. It has enabled me to lose 22 pounds, and I am now only one pound above my ideal weight (185 pounds). That is great, although I have had to buy new clothes and belts. Lol! My insulin resistance has been decreased, and my insulin sensitivity has increased. That is also good.
Metformin was initially introduced as a med to help with weight loss. Later on, it was found to help with with IR. It has caused me to lose some of my appetite, and I don't want to eat as much now. At one time I was losing an average of two pounds per week. To keep from dropping below my ideal weight, I had to increase my carb intake from 130 to 150 carbs per day. My weight has now stabilized. I don't want to eat that many carbs, and sometimes I have to eat when I am not hungry. That is annoying! If I lower my carb intake, then my weight drops too. I have tried lowering my Met dosages, but then my IR increases, and my BG numbers rise a lot. I am taking 1000 mg of Met in the morning and evening.
While using Avandia my BG's were very good, and I stayed in the interval 70-130 about 90% of the time. I have used Met for 15 months, and have a lot more highs and lows than before. My BG's are now in the 70-130 range only 66% of the time. BG's as low as the high 30s, and as high as the 170s are happening. I rarely had numbers like that while on Avandia. I am now on the roller coaster with my BG's, like I was before pumping.
During the first few years of the new century, I was diagnosed with some spots of neuropathy in both eyes, and neuropathy in my feet. That was caused by the unstable control, and the roller coaster I was experiencing. Complications can occur for that reason, even when the A1c is good. My A1c was below 6.0 for several years when those complications were diagnosed. After using a pump for a few months my BG's stabilized a lot, and my retinopathy disappeared. My neuropathy was still there, but the symptoms rarely appeared. The pain was gone. Pumping is great!
Now, while using Met, my roller coaster control has returned, and I am concerned that my retinopathy, and neuropathy pain may return too. My doctor says he has no other med to offer to help me with my IR. Avandia and Actos have both caused damage to many diabetics, so Met seems to be my only choice. I have tweaked the heck out of my pump, trying to get more stable control. It was easy with Avandia, but seemingly impossible with Metformin. I am apparently stuck with Met, and with the more unstable control. I am expecting those complications to return at any time now. Call me a pessimist, but this happened in the past, and it may happen again.