Successful treatment of severe lactic acidosis caused by a suicide attempt with a metformin overdose.

Metformin-associated lactic acidosis is a very rare but critical condition. It is seen in patients with type 2 diabetes mellitus who take metformin and attempt suicide with a metformin overdose. Here, we report a 43-year-old woman with type 2 diabetes mellitus and chronic renal insufficiency who developed hypoglycemia, hypothermia, tachycardia and lactic acidosis after a suicide attempt with a metformin overdose. She was successfully treated by continuous venovenous hemofiltration, and adequate hemodynamic and ventilatory support. Although metformin does not usually cause hypoglycemia when administered as monotherapy, hypoglycemia can occur in a condition coexistent with lactic acidosis secondary to metformin overdose. Metformin intoxication should be suspected when patients present with high anion gap metabolic acidosis after attempting suicide by ingesting drugs, particularly when comorbidities such as renal failure are present. Early diagnosis and rapid correction of the metabolic acidosis using hemodialysis or hemofiltration, together with concomitant cardiovascular support, and maintenance of blood glucose and core body temperature, provide the possibility of a positive outcome.