Erectile dysfunction as a possible important side effect of metformin: A case report.

Metformin-induced sexual dysfunction is rare in patients with diabetes mellitus. Herein, we present the case of a 57-year-old man newly diagnosed with type 2 diabetes mellitus who developed erectile dysfunction following treatment with metformin 500 mg BD. Prior to taking metformin, he had well-controlled hypertension, hyperlipidaemia and normal sexual function.