Lactic Acidosis and Rhabdomyolysis are Rare Complications of Metformin Toxicity, a Case Report.

Metformin is a widely used oral hypoglycemic agent in type 2 diabetes with a good safety profile. Overdose of metformin results in metformin-associated lactic acidosis (MALA), causing circulatory failure and multiorgan dysfunction. However, rhabdomyolysis is not a known feature of MALA. Here, we report a case of a 38-year-old woman who took 60g of metformin, causing shock, hypoglycemia, acute kidney injury, hepatitis, and rhabdomyolysis (creatine phosphokinase more than 24000 IU/L). There were no co-ingested medications other than metformin. She was treated with intravenous bicarbonate, vasopressors, continuous venovenous hemodiafiltration, and intermittent haemodialysis but not ventilated. She recovered with normal renal function. There were only three patients with MALA-associated rhabdomyolysis described in the literature. The patient who only took metformin without co-ingestion of other poisons had a creatine phosphokinase level of less than 3000 IU/L but was intubated and ventilated. Rhabdomyolysis can be a complication of MALA.