title: Intake of grapefruit juice alters the metabolic pattern of cyclosporin A in renal transplant recipients.
abstract: OBJECTIVE
  The aim of the present study was to investigate the effect of grapefruit juice on the pharmacokinetics of cyclosporin A (CsA), as Sandimmun Neoral, and its main metabolites, M1, M9 and M4N, in renal transplant recipients.
  
  
  METHODS
  Ten renal transplant recipients, on CsA-based immunosuppressive therapy, were included in this open, randomized crossover study. Patients were given their individualized morning dose of CsA, administered with either 250 ml water or 250 ml grapefruit juice and 12-hour CsA pharmacokinetic investigations were performed. The 2 investigation days were separated by at least 7 days.
  
  
  RESULTS
  Administration of CsA with grapefruit juice compared with water significantly increased the area under the whole blood concentration versus time curve in the interval from 0-12 hours (AUC(0-12)) of CsA, by an average of 25 +/- 19% (p = 0.002). Intake of grapefruit juice did not have any significant influence on maximum whole blood concentration (Cmax) or time to Cmax (tmax) of CsA. AUC(0-12) and Cmax of M9 decreased significantly with intake of grapefruit juice, on average 22 +/- 11% (p = 0.0007) and 36 +/- 6% (p = 0.0001), respectively. AUC(0-12) of M1, however, was on average 13 +/- 14% (p = 0.02) higher upon co-administration of CsA with grapefruit juice as compared with water. The level of M4N was below the limit of quantification in most samples, and an effect of co-administration of CsA with grapefruit juice could not be determined for this metabolite.
  
  
  CONCLUSIONS
  The present study shows that co-administration of grapefruit juice with CsA compared with water affects the formation and/or elimination of the 2 metabolites M1 and M9 differently. In addition, administration of CsA with grapefruit juice compared with water induced a moderate, but significant increase in systemic exposure of CsA in renal transplant recipients.
authors.affiliation: Department of Pharmacology, School of Pharmacy, University of Oslo, Norway. monicahe@farmasi.uio.no
authors.forename: M
authors.initials: M
authors.lastname: Hermann
authors.forename: A
authors.initials: A
authors.lastname: Asberg
authors.forename: J L E
authors.initials: JL
authors.lastname: Reubsaet
authors.forename: S
authors.initials: S
authors.lastname: Sather
authors.forename: K J
authors.initials: KJ
authors.lastname: Berg
authors.forename: H
authors.initials: H
authors.lastname: Christensen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001628:Beverages; D032083:Citrus paradisi; D018592:Cross-Over Studies; D016572:Cyclosporine / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D018565:Food-Drug Interactions / Q000502:physiology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000097:blood / Q000493:pharmacokinetics*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014867:Water / Q000008:administration & dosage
chemical_list: D007166:Immunosuppressive Agents; D014867:Water; D016572:Cyclosporine