Hippokratia 2003, 7(4):168-172
Tacrolimus (FK506 or Prograf?) is a macrolidic antibiotic, which acts as a calcineurine inhibitor. Its pivotal mechanism of action is the blocking of calcineurin phosphatase activity and the subsequent production of IL-2 and other cytokine production1. It is ten to one hundred times more potent drug compared to cyclosporine in a weight 1/1 basis2. Tacrolimus may also inhibit nitric oxide synthetase activation3 and enhance apoptosis.