RESUMO
Background: Treatments of acne vulgaris commonly use antimicrobials and comedolytic agents. Considering bacterial resistance to topical antibiotics, the alternative treatment such as silver manufactured into nanoparticle receives an attention. Silver nanoparticle has an antibacterial effect against Propionibacterium acnes and anti-inflammation. Clinical study of silver nanoparticle gel for the treatment of acne vulgaris is limited. Objective: To compare the efficacy and safety between silver nanoparticle gel and 1% clindamycin gel both combine with 2.5% benzoyl peroxide for the treatment of moderate severity of acne vulgaris. Material and Method: This was an experimental, double-blinded, randomized-controlled study. Sixty-four moderately severe acne patients were enrolled. They were randomized to receive either silver nanoparticle gel with 2.5% benzoyl peroxide or clindamycin gel with 2.5% benzoyl peroxide (32 patients each). The clinical outcomes were evaluated for inflammatory and non-inflammatory acne count, acne redness, the patients' satisfaction and patients' Dermatology Life Quality Index (DLQI) at the baseline, 2, 4, 6 and 8-week visit. Results: After 8 weeks of follow-up period, the average mean percent change from the baseline of non-inflammatory and inflammatory acne counts were gradually declined in both silver nanoparticle and clindamycin group. At the study endpoint (8-week visit), average mean percent change from the baseline of inflammatory acne count was slightly better reduction in silver nanoparticle group (79.7%) than clindamycin group (72.6%) with no significant difference (p = 0.18). The average mean percent change from the baseline of non-inflammatory acne count reduction was also no difference from silver nanoparticle and clindamycin group (61.1% and 66.8% respectively, p = 0.22). For clinical erythema score and Mexameter erythema index to evaluate acne redness were no statistical difference between the 2 groups. Moreover, the patients' satisfaction to study medication and their quality of life of patients (DLQI score) were reported with better improvement from the baseline in both groups but there was no statistical significant difference. Except for average mean, patients' satisfaction to acne severity at 6-week visit showed that silver nanoparticle group had better satisfaction score than clindamycin group (4.6±0.6 vs. 4.2±0.6) with statistical significance (p = 0.01). Common adverse effects were skin dryness (28.1%) and skin irritation (4.7%) which might be caused by 2.5% benzoyl peroxide. There was no adverse effect for silver nanoparticle gel from the present study. Conclusion: Silver nanoparticle gel is effective with good safety profile for the treatment of acne vulgaris. The present study demonstrated that there were no clinical significant differences between silver nanoparticle gel and clindamycin gel for the treatment of moderate severity of acne vulgaris when use in combination with 2.5% benzoyl peroxide. The clinical application as alternative treatment for acne is advised.