Metformin (Glucophage)

Treatment of type 2 DM, particularly in overweight pts, when dietary management and exercise alone do not result in adequate glycemic control.

A reduction of diabetic complications has been shown in overweight type 2 diabetic pts treated with metformin as first-line therapy after diet failure.

Very common: Nausea, vomiting, abdominal pain

Common: Taste disturbance

Very rare: Lactic acidosis

Hypoglycemia (rare)

Metformin-associated lactic acidosis: The summary of product characteristics states that “Metformin hydrochloride should be discontinued 48 h before elective surgery under general, spinal or epidural anaesthesia. Therapy may be restarted no earlier than 48 h following surgery or resumption of oral nutrition and only if normal renal function has been established.” This is due to the fear of metformin-associated lactic acidosis. It is unproven whether metformin causes the lactic acidosis or whether it is the diabetes that causes it.