ObjectiveTo investigate the influence of hydrogen peroxide (H2O2) on the antifungal effect of 5 azoles (fluconazole, itraconazole, ketoconazole, miconazole, and sulconazole) against drug-resistant Candida albicans. MethodsEight strains of drug-resistant Candida albicans and two strains of drug-susceptible Candida albicans were used in this study. The minimal inhibitory concentration for 80% (MIC80) of each individual antifungal drug was determined by broth microdilution antifungal susceptibility testing; the MIC80 of the antifungal drug was also determined when in combination with H2O2 by checkerboard microdilution assay. Then the fractional inhibitory concentration index (FICI) was calculated to decide the synergism, indifference, or antagonism of H2O2 with azoles. ResultsThe FICI values of the 8 drug-resistant strains for combination of H2O2 with 5 azoles were less than 0.5, indicating the presence of synergism. The FICI values of the two drug-susceptible strains were between 0.5 and 2, indicating the presence of indifference. ConclusionH2O2 and the azoles (fluconazole, itraconazole, ketoconazole, miconazole and sulconazole) possess synergism effect against drug-resistant Candida albicans.