Azanza JR, Garcia-Quetglas E, Sadaba B. Farmacología de los azoles. Rev Iberoam Micol 2007 Sep 30;24(3):223-227.
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.