Metformin in skin diseases: the role of gut microbiota and immune response.

Metformin is one of the most commonly prescribed drugs for the treatment of type 2 diabetes (T2D). Its mechanism of action involves lowering blood glucose levels by enhancing peripheral tissue sensitivity to insulin, inhibiting hepatic glucose production, and decreasing intestinal glucose absorption. Recent research has shown that metformin may also have therapeutic potential beyond diabetes, including the treatment of chronic pain, cancer, and polycystic ovary syndrome. Additionally, metformin is used in managing various skin diseases such as atopic dermatitis (AD), allergic contact dermatitis (ACD), and psoriasis. It has also been found to influence skin aging processes and promote wound healing. These effects may be attributed to metformin’s immunomodulatory properties and its ability to modulate the gut microbiota. The aim of this review is to summarize the current evidence on the effects of metformin on gut microbial composition and the immune system, as well as its potential role in the treatment of skin diseases.