We examined the efficacy and toxicity of single daily dosing (SDD) of aminoglycosides for febrile, immunocompromised adults by systematically reviewing four randomized, controlled trials of SDD vs. standard dosing regimens. We assessed the methodological quality of each study and extracted data pertaining to efficacy and toxicity outcomes. Pooled risk ratios for the efficacy outcomes were bacteriologic cure, 1.00 (95% confidence interval [CI], 0.86-1.16); clinical cure, 0.97 (95% CI, 0.91-1.05); and mortality, 0.93 (95% CI, 0.62-1.41). The pooled nephrotoxicity risk ratio was 0.78 (95% CI, 0.31-1.94). Only one study assessed ototoxicity. Although our study was limited by the small number of trials available for review, the results suggest that SDD of aminoglycosides may be efficacious for febrile, immunocompromised patients. Additional studies are necessary for more precise quantification of the mortality and toxicity risk ratios.