Hypersensitivity reaction with metformin: a case report

Abstract

Metformin is a biguanide derivative widely used for treatment of diabetic patients. The most common toxic effects of metformin are gastrointestinal (anorexia, nausea, vomiting, abdominal discomfort and diarrhoea). As with other drugs, allergic reactions can occur with metformin also, but these are very rare. A case of hypersensitivity reaction with metformin was reported in adverse drug monitoring centre. A 59-year-old female, newly diagnosed case of diabetes mellitus II, started on metformin tablet 500 mg twice daily, developed purpuric skin lesions on her arms, legs and back few days after starting the drug. metformin was stopped and patient was put on glimepiride tablet. The lesions slowly started subsiding after stopping metformin.

Cutaneous Reactions to Antidiabetic Agents: A Narrative Review

“…The most commonly reported reaction to metformin found was leukocytoclastic vasculitis (LCV). All six reports involved women from 33-60 years old and were biopsy proven LCV with a full work-up excluding other possible causes of LCV [15][16][17][18][19][20]. Described as hemorrhagic papules, vesicles and bullae, the vasculitis started on each of their legs and in some cases progressed to other areas of the body including trunks and forearms.…”

“…Described as hemorrhagic papules, vesicles and bullae, the vasculitis started on each of their legs and in some cases progressed to other areas of the body including trunks and forearms. Discontinuing metformin and starting prednisone significantly improved the eruption [15][16][17][18][19][20].…”