Two patients with renal failure and fluconazole resistant but flucytosine susceptible Candida deep infection were successfully treated with the combination of the two drugs. In vitro susceptibility, determined by microdilution and time-kill methods, and fungostatic activity of the serum showed an additive interaction of fluconazole and flucytosine. In the event of infections by Candida isolates resistant to fluconazole but susceptible to 5-fluorocytosine, the combination of these drugs may be a possible therapeutic choice.