Clinical and dermoscopic evaluation of combined (salicylic acid 20% and azelaic acid 20%) versus trichloroacetic acid 25% chemical peel in acne: an RCT.

Background: Combined azelaic acid (AA) and salicylic acid (SA) have not been previously used for acne. Objective: To compare the efficacy of this combination versus trichloroacetic acid (TCA) 25% peel in acne. Methods: Thirty-four patients were included in this trial. Patients received four sessions 2 weeks apart. The combined solution was applied to one side of the face, while TCA was applied to the other. Our outcomes were physician-reported clinical improvement, dermoscopic assessment of the erythema and patient's satisfaction. Results: After two sessions, a significant clinical improvement was observed in non-inflammatory lesions in the TCA-treated side-treated TCA and in inflammatory lesions in the SA/AA-treated side. At the end, both modalities led to significant improvement, with no significant difference in between. Patients reported more discomfort with the TCA-treated side. There was no significant different clinical improvement in both treated sides as regards SPT. Erythema improved in both sides. Patients were more satisfied by the SA/AA-treated side. Conclusion: Chemical peeling is effective in controlling mild-moderate acne in SPT III-IV. Combined SA 20% and AA 20% are recommended at early stage of treatment if patients have more inflammatory lesions, while TCA is recommended if patients have more non-inflammatory lesions.