I have been taking Metaformin off and on for the past 10, years per Type II Diabetes. I was warned of the stomach symptoms, but unaware of the hearing issues. Understand that it is well tolerated even up to 3000 units per day. However this is for Diabetes. Funny thing and due to my anxiety, is that while I do not seem to have any adverse symptoms taking this prescription, any other prescribed drug causes symptoms which can only be traced to my anxieties over taking drugs. This is not to say that symptoms cannot be real, but for me, most are in my head. I would check with your MD, as I too started off on time released 500mgs and have periodic blood checks. Best

I have been taking Metformin 2000mg twice a day for over a year now for Type II and PCOS. I am still tired all the time and have occastional upset stomach. I also just recently noticed plugged ear feelings. I've gained about 20lbs. but also quit smoking around the time I started Metformin.
Stephy - If you don't have diabetes now, Metformin could prevent you from getting it. Keep taking it! The side effects get better!! I am 34 and still trying to have a baby because of PCOS.