Clinical and Dermoscopic Evaluation of the Effectiveness of Metformin versus Pioglitazone in Acanthosis Nigricans: A Randomised Controlled Trial

Metformin and pioglitazone both significantly improved AN clinically and dermoscopically, with no significant differences in efficacy between them. Metformin is more effective in reducing weight and body mass index, and is suitable for overweight patients. Pioglitazone is an alternative for those intolerant or unresponsive to metformin. Dermoscopic parameters can indicate early treatment response before visible clinical improvement.