Abstract
BACKGROUND: Intense pulsed light (IPL) is a promising treatment method for acne vulgaris. However, no studies have directly compared IPL with light-emitting diode (LED) phototherapy when used as adjuncts to systemic doxycycline or isotretinoin in acne treatment. OBJECTIVE: This study aimed to evaluate the efficacy and safety of IPL vs. LED phototherapy as an early intervention strategy, combined with doxycycline or isotretinoin, in patients with acne vulgaris. METHODS: A prospective, split-face, controlled pilot study was conducted. Forty Asian participants with moderate-to-severe acne received a 4-week continuous split-face treatment to assess the rapid response of the two phototherapy modalities in the early phase of treatment. The protocol involved weekly IPL (400-600 nm/800-1,200 nm filter) on one side of the face and twice-weekly red-blue LED phototherapy on the contralateral side. Outcomes were assessed using the investigator-assessed Global Acne Grading System (GAGS) scores and a patient-reported Likert satisfaction scale. RESULTS: Based on investigator assessments, IPL and LED produced comparable improvement in acne severity, demonstrating that significant improvement can be achieved early in the treatment course. In the doxycycline group, the mean improvement was 46.08% on the LED-treated side and 48.82% on the IPL-treated side; in the isotretinoin group, the mean improvement was 48.62% on the LED-treated side and 46.69% on the IPL-treated side. Patient satisfaction tended to be slightly higher on the IPL-treated side during this early stage. On the LED-treated side, "very satisfied" was reported by three participants (15%) in the doxycycline group and four participants (20%) in the isotretinoin group. Overall, there was no significant difference in efficacy between the two devices at this early time point (p > 0.05). In terms of safety, no serious adverse events were observed in either group. Transient adverse reactions (pain, erythema, and edema) occurred more frequently on the IPL-treated side. CONCLUSION: IPL is comparable to LED in clinical efficacy for the treatment of moderate-to-severe acne in Asian patients when combined with doxycycline or isotretinoin, with both modalities demonstrating rapid symptomatic improvement early in the treatment course. CLINICAL TRIAL NUMBER: Identifier, ChiCTR2500107064.