RESUMEN
BACKGROUND: Acanthosis nigricans is a non-inflammatory skin pigmentary disorder characterized by a dark, velvety appearance, primarily observed in the neck and axillary areas. It is commonly associated with obesity, diabetes, and insulin resistance. Although the primary treatment is correcting the underlying disorders, many aesthetic modalities have been established to improve appearance owing to cosmetic concerns. AIMS: We aimed to compare and investigate the effectiveness and side effects of tretinoin 0.05% and glycolic acid 70% in treating acanthosis nigricans lesions of the axillary and neck area. METHODS: This single-blinded, randomized trial recruited patients with neck or axillary involvement. Each patient was randomized to use cream tretinoin 0.05% every other night on one side, while the other side was treated with glycolic acid 70%, which was applied every 2 weeks at the clinic for four consecutive sessions. The study duration was 8 weeks, and patients were evaluated every 2 weeks based on their response to treatment, satisfaction, and side effects. RESULTS: Thirty patients, including 14 with neck lesions and 16 with axillary lesions, were included. Tretinoin was significantly more effective for axillary lesions in terms of treatment response and patient satisfaction (p = 0.02 and p = 0.008, respectively). It was also shown that as the severity of the lesions increased, the response to treatment and patient satisfaction decreased, specifically when treating axillary lesions with glycolic acid (p = 0.02 and p = 0.03, respectively). CONCLUSION: Neither method was significantly effective for neck lesions. However, tretinoin 0.05% was shown to be more efficacious in treating axillary lesions of acanthosis nigricans, despite causing minimal side effects.