Tacrolimus: review of pharmacokinetics, pharmacodynamics, and pharmacogenetics to facilitate practitioners' understanding and offer strategies for educating patients and promoting adherence.

Kidney transplantation requires lifelong immunosuppression with agents that prevent allograft rejection. Immunosuppressive regimens typically include a steroid, an immune modulator (eg, azathioprine, mycophenolate mofetil, or mycophenolate sodium), and a calcineurin inhibitor, either cyclosporine or tacrolimus. Tacrolimus is metabolized by cytochrome P450 3A4 in both the liver and small intestine.