Hello
As you mentioned that there was cardiac ablation in 2010 , so may be you are taking some medicines for heart .
So there are certain drugs which interact with metfomin , these drugs are:
Addictive effects of metformin , Glycaemic control may be affected by diuretics,
corticosteroids , phenothiazines , thyroid products , oral contraceptives , phenytoin , nicotinic acid , sympathomimetic , Calcium channel blockers,
chlorpromazine & isoniazide.
Metformin effects may be increased by ACE inhibitors, MAOIs , cemitidine increase the serum level of metformin.
These are side effects ;
Anorexia , nausea , vomiting , diarrhea, weight loss , flatulence, occasional metallic taste, WEAKNESS( DEBILITATING EFFECT ) , hypoglycemia , rash, malabsorption of B 12 ,
chest discomfort ,
lightheadedness , indigestion, abdominal discomfort,
lactic acidosis in renal failure & alcoholism.
So you better judge about insurance company .
Hope this will be helpful for you.