摘要： BACKGROUND Nonablative 1,450-nm diode laser (DL) and visible blue light (BL) have been effectively used for acne with superior safety pro?les. OBJECTIVE To evaluate synergistic effects of sequential DL and BL application for acne. METHODS A 20-week, randomized split-face study was conducted to compare clinical courses between 2 facial sides either receiving sequential application of DL and BL or BL alone in 24 patients with mild to moderate facial acne vulgaris. Patients were scheduled to receive 3 consecutive sessions at 4-week intervals. Objective assessments, including revised Leeds grades, lesion counts, and sebum output measurements, and patients’ subjective satisfaction were investigated. RESULTS Both combination and BL sides demonstrated steady improvement of in?ammatory acne lesions with 62.3% and 35.2% decreases at the 12-week follow-up visit compared with baseline respectively. For nonin?ammatory lesions and seborrhea, only combination regimen demonstrated improvement. Patients’ subjective assessments paralleled objective ?ndings. For safety pro?les, no severe adverse effect was observed on both sides, and mild symptoms resolved spontaneously within a day. CONCLUSION The combination regimen demonstrated synergistic ef?cacies for acne and seborrhea, with satisfactory safety pro?les. Therefore, a few sessions of these light-based applications would be a viable option for acne treatments.