Lack of effect of fluconazole on the pharmacokinetics of rifampicin in AIDS patients.

To evaluate the effect of fluconazole on rifampicin pharmacokinetics, eleven AIDS patients received rifampicin (300 mg/day; days 1-28) and fluconazole (400 mg/day; days 15-28). Rifampicin pharmacokinetics were studied on days 14 and 28. There was no significant effect of fluconazole on rifampicin pharmacokinetics. These results suggest that rifampicin dosage adjustment may not be necessary when this drug is coadministered with fluconazole.