A new therapeutic option for facial seborrhoeic dermatitis: indole-3-acetic acid photodynamic therapy.

BACKGROUND: Indole-3-acetic acid (IAA) is a newly introduced photosensitizer of photodynamic therapy (PDT) for acne, presenting sebum-reducing, anti-inflammatory and antimicrobial activity. OBJECTIVE: This study was designed to evaluate the efficacy and safety of IAA-PDT in the treatment of facial seborrhoeic dermatitis. METHOD: In this prospective, single-blinded, 6-week trial, 23 patients with facial seborrhoeic dermatitis were treated with IAA-PDT with green light (520 nm) three times with 1-week intervals. Patients were evaluated at baseline, week 1, 2, 3 and week 6 (3 weeks after last treatment). Efficacy was determined by Seborrhoeic dermatitis Area and Severity Index (SASI), patient's assessment of the symptoms (4-point scale of itchiness, burning, erythema, scale and tightness), sebum secretion rate (measured with Sebumeter(®)), Erythema Index (EI, measured with Mexameter(®)) and physician's photographic assessment. Safety was evaluated by questionnaire at each visit. RESULT: For the 22 subjects completing the trial, SASI and total symptom significantly improved at week 2, which lasted until week 6. Sebum excretion was significantly reduced at week 2 and stayed reduced until week 6. EI presented continuous reduction throughout the study. Photographic assessment showed significant improvement at each visit. The procedure was painless, and no adverse event was observed during and after the treatment. CONCLUSION: IAA-PDT is a safe and effective therapeutic option for facial seborrhoeic dermatitis.