Effects of multiple oral dosing of itraconazole on the pharmacokinetics of cyclosporine in cats.

Itraconazole (Icz) has been known to increase the cyclosporine (CsA) trough level in human transplant patients. However, the interaction of Icz with CsA has not been reported in cats. In this study, the effect of multiple dosing of Icz on the pharmacokinetics of CsA in three healthy cats was investigated. The treatments included CsA 5mg/kg alone and CsA 5mg/kg+multiple-dose of Icz 10mg/kg. Co-administration of Icz with CsA resulted in significant increases of oral bioavailability of CsA. The results of our study suggest that administration of multiple therapeutic doses of Icz may decrease the required CsA dosage in CsA-based immunosuppressive therapy used for renal transplantation in cats.