Efficacy and safety of oral doxycycline for acne vulgaris treatment: A systematic review and meta-analysis.

Doxycycline is commonly used to manage acne vulgaris (AV), but comprehensive comparisons of its efficacy and safety against alternative treatments remain limited. This study aimed to systematically evaluate and compare the efficacy and safety of oral doxycycline with other therapeutic options for AV treatment. A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted following PRISMA guidelines. Literature searches were performed in PubMed/MEDLINE, Embase, Cochrane CENTRAL, Scopus, Web of Science, and Google Scholar up to March 2024, using Medical Subject Headings (MeSH) and relevant free-text terms (e.g., "doxycycline AND acne vulgaris"). The primary outcomes were treatment success, change in inflammatory lesion count, and Global Acne Grading System (GAGS) scores, while safety outcomes focused on the incidence of reported adverse events. The risk of bias across studies was evaluated using the Cochrane ROB-2 tool, and meta-analyses were conducted using random-effects models to account for expected heterogeneity. A total of 23 RCTs comprising 2,672 patients were included. Doxycycline showed similar efficacy to azithromycin in achieving treatment success (OR 1.28; 95% CI [0.54, 3.04], p = 0.57; I2 = 60%), with no significant difference in inflammatory lesion reduction (MD -0.71; 95% CI [-8.61, 7.19], p = 0.86; I2 = 97%). However, other treatments (e.g., isotretinoin, silymarin) demonstrated greater improvements in GAGS scores (MD 1.76; 95% CI [1.53, 2.00], p < 0.00001; I2 = 53%). More adverse events, particularly gastrointestinal and dermatological, were reported with doxycycline. While effective, its safety profile and comparative performance warrant further investigation through high-quality RCTs.