Clinical assessment of topical erythromycin gel with and without zinc acetate for treating mild-to-moderate acne vulgaris

Purpose: Erythromycin is an effective topical antibiotic for treating mild-to-moderate inflammatory acne vulgaris, especially papules acne during puberty as well as papules - pustular acne in adult women. Erythromycin is a macrolide antibiotic that has long been used as a topical dosage form to treat acne. It has favorable effects in resolving inflammatory acne lesions not only by reducing Propioni bacterium acnes density, but also by directly inhibiting neutrophil chemotactic factors and reactive oxygen species (ROS) production. Zinc, a metallic element has bacteriostatic activity against Propioni bacterium acnes. Combining zinc with antibiotic (erythromycin) can reduce antibiotic resistance and increase antibiotic absorption in-to the skin.Material and methods: In the present study, erythromycin (2% w/v) with zinc acetate (1.2% w/v) as 'topical gel' and erythromycin (2% w/v) gel alone were evaluated for treating mild to moderate inflammatory acne vulgaris. This double-blind study was carried out on 102 patients 13–25 years of age, divided into two groups. The group A received erythromycin and group B received erythromycin with zinc acetate topical gels during 3 weeks. Acne grading and lesion counts for comedones, papules and pustules were performed during each visit zero, first, second and third weeks.Results: Erythromycin treatment (with zinc acetate) gel showed to be more effective than erythromycin (alone) gel with respect to reducing the number of acne lesions and severity grade of acne.Number of lesions and severity of acne were significantly reduced at the end of 3rd week in both groups (p < .001). Conclusions: In conclusion, it can be stated that erythromycin with and without zinc acetate was clinically effective, and both formulations produced a significant reductions in acne grading as well as inflamed and noninflamed lesion counts (p < .000). Statistically, there was no significant difference between formulation A and B.