[Pharmacology of azoles].
Azole antifungals have different pharmacokinetic characteristics: complete oral absorption for Voriconazole, and to a lesser extent for fluconazole. The absorption of posaconazole and itraconazole increases with food intake. All of them have high tissue distribution with low plasma concentrations, especially low in the case of posaconazole and itraconazole. Posaconazole and itraconazole have high plasmatic protein binding and consequently both have a very low free fraction. Elimination of azole antifungals is through a metabolic pathway with CYP450 isoenzymes, and has a non linear pharmacokinetics with a high risk of interation with other drugs since azoles have the ability of CYP450 isoenzymes inhibition. Possibly the parameter that defines more precisely their efficacy is AUIC with an optimum value near 20, although cut-off values must be defined since some azoles may have difficulty to reach this value.
Azanza
José Ramón
JR
Servicio de Farmacología Clínica, Clínica Universitaria de Navarra, Facultad de Medicina Universidad de Navarra, Pamplona, Navarra, Spain. jrazanza@unav.es
García-Quetglas
Emilio
E
Sádaba
Belén
B
D000328:Adult; D000935:Antifungal Agents / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D001682:Biological Availability; D001711:Biotransformation; D002648:Child; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004347:Drug Interactions; D006801:Humans; D014230:Triazoles / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use
D000935:Antifungal Agents; D014230:Triazoles; D003577:Cytochrome P-450 Enzyme System