BACKGROUND Therapeutic drug monitoring and Model-informed precision dosing allow dose individualization to increase drug effectivity and reduce toxicity. OBJECTIVE To evaluate the available evidence on the clinical efficacy of individualized antimicrobial dosing optimization. METHODS Data sources: PubMed, Embase, Web of Science, and Cochrane Library databases from database inception to 11 November 2022. METHODS Published peer-reviewed randomized controlled trials. METHODS Human subjects aged ≥18 years receiving an antibiotic or antifungal drug. METHODS Patients receiving individualized antimicrobial dose adjustment. Cochrane risk-of-bias tool for randomized trials. The primary outcome was the risk of mortality. Secondary outcomes included target attainment, treatment failure, clinical and microbiological cure, length of stay, treatment duration, and adverse events. Effect sizes were pooled using a random-effects model. Statistical heterogeneity was assessed by inconsistency testing (I2). RESULTS Ten randomized controlled trials were included in the meta-analysis (1241 participants; n = 624 in the individualized antimicrobial dosing group and n = 617 in the control group). Individualized antimicrobial dose optimization was associated with a numerical decrease in mortality (risk ratio [RR] = 0.86; 95% CI, 0.71-1.05), without reaching statistical significance. Moreover, it was associated with significantly higher target attainment rates (RR = 1.41; 95% CI, 1.13-1.76) and a significant decrease in treatment failure (RR = 0.70; 95% CI, 0.54-0.92). Individualized antimicrobial dose optimization was associated with improvement, but not significant in clinical cure (RR = 1.33; 95% CI, 0.94-1.33) and microbiological outcome (RR = 1.25; CI, 1.00-1.57), as well as with a significant decrease in the risk of nephrotoxicity (RR = 0.55; 95% CI, 0.31-0.97). CONCLUSIONS This meta-analysis demonstrated that target attainment, treatment failure, and nephrotoxicity were significantly improved in patients who underwent individualized antimicrobial dose optimization. It showed an improvement in mortality, clinical cure or microbiological outcome, although not significant.