Thanks everyone for your responses.

I now understand that not everyone loses weight with Glucophage. I haven't experienced bad side effects with Glucophage, except for diarrhea - but it only happened in the first 3 days and then everything was normal again. At first I thought that the medicine isn't effective because the side effect stopped.

I really want to lose weight so I modified my diet. I went on a 2-day fasting and then after that, I've maintained a low-calorie diet. I've lost 4 kilos in 1 month. I stopped taking glucophage now and I hope this is okay. I haven't seen my doctor lately, too.

But does anyone of you know if it's okay to stop taking medicines with a modified diet?