Tacrolimus (FK506) is an immunosuppressive drug that is given orally or intravenously to patients who have had a kidney, liver, heart, or other organ transplant. Normally, a person’s immune system would recognize the new organ as foreign and begin to attack it. Tacrolimus limits this response and helps to prevent organ rejection by reducing the activity of T-lymphocytes. Therefore levels may be measured in order to establish the correct dose, maintain therapeutic levels and detect toxic levels
Generally, the lower the level the better, provided the patient is NOT rejecting. There is a significant clinical component in the interpretation of results.
It is important to monitor levels of tacrolimus for several reasons:
Trough sample required.
Reference or therapeutic ranges are not reported as therapeutic target ranges are applied on an individual basis dependent upon specialty, dosing, period in treatment regime and clinical status. Further advice can be obtained from the appropriate speciality.