Tacrolimus: A Review of Laboratory Detection Methods and Indications for Use.

Tacrolimus (Tac) is an immunosuppressive drug that is used in preventing organ and tissue rejection in patients after transplantation. Tac administration requires frequent and diligent monitoring by physicians to ensure proper dosage and to limit the potential for harmful adverse effects, which can include renal damage, neurotoxicity, and other serious adverse events. Tac is a calcineurin inhibitor, which suppresses the function of T-cells. Its success as an immunosuppressive agent has been well documented in preventing graft-vs-host disease in several types of organ transplants. This literature review will discuss Tac metabolism and its role in preventing tissue and organ transplant rejection. A variety of detection techniques used in the clinical laboratory, including dried-blood-spot analysis, liquid chromatography-tandem mass spectrometry, and immunoassay also will be discussed.