Metformin, primarily used in patients with diabetes, has been reported to be a valuable option in the management of cutaneous diseases. Accumulating evidence suggests the efficacy of this agent in hormonal acneand acanthosis nigricans. This could be attributed to its vital role in improving hyperinsulinemia. It has been seen that metformin improves hyperinsulinemia by its action on glucose transporter 4 (GLUT 4), a key factor underlying the development of acanthosis nigricans.¹

The antiandrogenic properties of metformin make it an enticing add-on drug to the conventional management of hirsutism associated with polycystic ovarian syndrome. A study performed by Tan and co-workers evaluated the effects of metformin therapy on 188 females suffering from polycystic ovary syndrome. In this study, lean, overweight, and obese patients were administered metformin in a dosage ranging from 500 to 1000 mg twice daily for 6 months. The results showed improvement in acne severity in all three groups at the end of the study. In addition, favorable outcomes were reported with respect to insulin resistance, menstrual irregularities, and serum testosterone levels.¹

Furthermore, metformin also helps in controlling hidradenitis suppurativa, a disease whose standard treatment is not effective.^1,2 A study evaluated the clinical efficacy of metformin in 25 patients with hidradenitis suppurativa, who did not respond to standard therapies. The results showed that over a period of 24 weeks, clinical improvement was seen in 18 patients. The Dermatology life quality index also improved significantly in 16 patients. The side effects were minimal and compliance was good.²

Eruptive xanthoma is another cutaneous disorder in which efficacy of metformin has been observed. In these patients, metformin acts by activating adenosine monophosphate-activated protein kinase in hepatocytes, thereby decreasing the activity of acetyl-CoA carboxylase and thus, heralding oxidation of fatty acids and reduction in expression of lipogenic enzymes. Besides these conditions, there have been encouraging reports on its benefits in cutaneous malignancies and hyperpigmentary disorders.¹

Based on the aforementioned data, it can be stated that metformin displays a potential to manage various cutaneous disorders, especially those associated with hyperinsulinemia and hyperandrogenism.^1,2

References

1. Bubna AK. Metformin - For the dermatologist. Indian Journal of Pharmacology. 2016 Jan-Feb;48(1):4-10.
2. Verdolini R, Clayton N, Smith A, et al. Metformin for the treatment of hidradenitis suppurativa: a little help along the way. 2013;27(9):1101-1108.