<unk>  is a hypoglycemic agent that is FDA approved for the treatment of type 2 diabetes mellitus. There is a Black Box Warning for this drug as shown here.  Common adverse reactions include cobalamin deficiency, diarrhea, flatulence, indigestion, malabsorption syndrome, nausea, vomiting, asthenia, headache.
Metformin
Buformin
Phenformin
Rosiglitazone
Glyburide
Pioglitazone
Liraglutide
Miglitol