Photodynamic therapy of acne

Abstract

Acne is one of the most common skin conditions in the world. A number of studies have shown that photodynamic therapy (PDT) is safe and effective for both inflammatory and non-inflammatory acne and can significantly improve skin conditions in this disease. The effectiveness of PDT against acne is mainly due to a decrease in the amount of sebum produced by the sebaceous glands due to a decrease in their activity as a result of direct photodynamic damage to the sebaceous glands, eradication of Cutibacterium acnes, and a decrease in the level of hyperkeratosis. Compared with systemic drug therapy, PDT treatment of severe acne has the following advantages: fast results, high efficiency, high selectivity, no systemic adverse reactions and drug resistance, and low recurrence rate. Most often for PDT in patients with acne, drugs based on 5-aminolevulinic acid (5-ALA) and its methyl ester (ME-ALA) are used. At the moment, there are no unified recommendations on PDT regimens for the treatment of this skin pathology. Various studies demonstrate the high efficiency of PDT with a wide range of doses of 5-ALA (3-20%) and ME-ALA (4-16%), light doses (15-120 J/cm2 ), and exposure time (30-90 min). The general trend in studies by different authors is that gentle low-intensity PDT regimens for acne demonstrate the same high efficiency with a significant reduction in pain during irradiation and local skin reactions (erythrema, edema, and hyperpigmentation).