Here we have outlined a case in which lactic acidosis developed during treatment of a diabetic patient in whom there were no contraindications to metformin treatment. Lactic acidosis was caused by acute renal failure leading to metformin accumulation.
The acute renal failure was caused by a combination of dehydration due to a low intake of fluids when disabled decause of a fractured ankle, concomitant diuretic treatment of arterial hypetension and angiotensin - convertin enzyme inhibitor treatment.