title: Change of the blood concentration of tacrolimus after the switch from fluconazole to voriconazole in patients receiving allogeneic hematopoietic stem cell transplantation.
abstract: The purpose of this study was to assess the impact by switching co-administered triazole antifungal agent from fluconazole (FCZ) to voriconazole (VCZ) on the blood concentration of tacrolimus (FK506) in patients receiving allogeneic hematopoietic stem cell transplantation. We performed a retrospective study presented as case reports. The blood concentration of FK506 was increased after the switch from FCZ to VCZ, resulting in increase of the concentration/dose (C/D) ratio of FK506. Thus, the mean C/D ratios of FK506 with oral administration was surprisingly increased over 4.5-fold after the switch. Therefore, it was necessary to reduce the FK506 dose when co-administered FCZ is switched to VCZ. We should be careful when interpreting the results of these case reports; however, in some patients, it is recommended that the dose of FK506 be reduced to one-fifth after the switch.
authors.affiliation: Department of Pharmacy, Kagawa University Hospital, Japan. khitochi@med.kagawa-u.ac.jp
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kawazoe
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Takiguchi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Noriyasu
authors.initials: N
authors.lastname: Fukuoka
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ohnishi
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Ishida
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Houchi
mesh_terms: D015725:Fluconazole / Q000008:administration & dosage*; D006801:Humans; D007166:Immunosuppressive Agents / Q000097:blood*; D011743:Pyrimidines / Q000008:administration & dosage*; D012189:Retrospective Studies; D033581:Stem Cell Transplantation; D016559:Tacrolimus / Q000097:blood*; D014230:Triazoles / Q000008:administration & dosage*; D065819:Voriconazole
chemical_list: D007166:Immunosuppressive Agents; D011743:Pyrimidines; D014230:Triazoles; D015725:Fluconazole; D065819:Voriconazole; D016559:Tacrolimus