title: Change in oral absorption of tacrolimus in a liver transplant recipient after reversal of jejunoileal bypass: case report.
abstract: BACKGROUND
  Jejunoileal bypass (JIB) was, at one time, a popular surgical technique for the treatment of morbid obesity. However, this operation was also associated with major complications. Consequently, many such procedures were eventually reversed. One of the most serious of these complications was liver failure. For those patients who developed cirrhosis, liver transplantation was one therapeutic alternative. Tacrolimus is one of the primary immunosuppressive agents used in liver transplantation. It is effective to prevent acute rejection episodes, but shows a narrow therapeutic index and can cause nephrotoxicity and neurotoxicity. This report describes the change in tacrolimus absorption that was observed after JIB reversal in a 57-year-old female liver transplant recipient.
  
  
  RESULTS
  Prior to JIB reversal, the mean tacrolimus dose was 7 mg twice daily with a whole-blood tacrolimus concentration ranging from 5.2 to 6.4 ng/mL. There was no appreciable peak in tacrolimus concentration, and the area under the concentration-time curve (AUC) was 10.9 ng/mL/h. After reversal, the daily tacrolimus dose was decreased to 5 mg twice daily, with a now-discernable peak concentration at 3 hours postdose. Furthermore, the AUC increased 90% to 20.7 ng/mL/h.
  
  
  CONCLUSIONS
  After JIB reversal, the patient showed higher systemic levels of tacrolimus and required lower steady-state doses. It is therefore imperative that such patients be monitored closely to avoid tacrolimus-related toxicity.
authors.affiliation: Department of Pharmacy, Division of Transplantation, University of Rochester Medical Center-Strong Memorial Hospital, Rochester, New York 14642, USA.
authors.forename: M
authors.initials: M
authors.lastname: Kelley
authors.forename: A
authors.initials: A
authors.lastname: Jain
authors.forename: R
authors.initials: R
authors.lastname: Kashyap
authors.forename: M
authors.initials: M
authors.lastname: Orloff
authors.forename: P
authors.initials: P
authors.lastname: Abt
authors.forename: K
authors.initials: K
authors.lastname: Wrobble
authors.forename: R
authors.initials: R
authors.lastname: Venkataramanan
authors.forename: A
authors.initials: A
authors.lastname: Bozorgzadeh
mesh_terms: D000284:Administration, Oral; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D007408:Intestinal Absorption; D007581:Jejunoileal Bypass; D016031:Liver Transplantation / Q000276:immunology*; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery; D012086:Reoperation; D016559:Tacrolimus / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use*
chemical_list: D007166:Immunosuppressive Agents; D016559:Tacrolimus