Metformin: Old Drug, New Therapeutic Potential in the Skin? A Brief Narrative Review.

Metformin, a well-established, first-line therapy for type 2 diabetes mellitus, is still gaining interest for its potential applications beyond glycaemic control. In addition to its insulin-sensitising effects, metformin exhibits anti-inflammatory, antioxidant, anti-proliferative, and immunomodulatory properties, rendering it a promising candidate for various dermatological conditions. Emerging evidence suggests that metformin may play a beneficial role in inflammatory skin diseases, such as acne, hidradenitis suppurativa, acanthosis nigricans, rosacea and psoriasis. Furthermore, recent studies highlight its potential in promoting wound healing and modulating skin ageing. This narrative review summarises current knowledge of the mechanisms of action of metformin in dermatology and explores its potential as a novel therapeutic approach for skin disorders.