Diabetic coma, ketoacidosis, severe infection, trauma or other severe conditions where metformin is unlikely to control hyperglycemia. Monitor renal function. Dehydration. Conditions associated w/ hypoxia eg, acute heart failure, recent MI or shock; excessive alcohol intake & hepatic impairment. Interrupt treatment 48 hr prior to & w/held at least 48 hr after contrast media exam. Annual monitoring of vit B12
conc during long-term treatment.