Three patients have been followed, each with impaired renal function. Fluconazole is excreted unchanged in the urine (>70%). Therefore it is necessary to do pharmacokinetic studies in these patients to determine the ideal dosing regimen required for anti-fungal activity. The analysis of fluconazole is by a HPLC method with sufficient sensitivity and accuracy to determine reliable pharmacokinetic estimates. Initial results indicate 1) A high correlation of creatinine clearance on fluconazole clearance, 2) A volume of distribution term correlating with ideal body weight, and 3) No change in these estimates with multiple dosing and steady-state.