FK506 test, also referred to as TAC test or tacrolimus test, is often conducted to determine the level of the drug tacrolimus in blood, thus establishing dosing regimen, maintaining therapeutic levels, and detecting toxic levels.
If you have started your tacrolimus therapy, you need to get tests frequently at first, and then monitor concentrations over time at regular intervals.
Test results are as follows:
- Higher concentrations of FK506 than normal therapeutic range increase the risk of associated toxicity such as kidney damage and nerves damage.
- Normal 12-hour trough concentrations of FK506 are 5.0-20.0 ng/ml; Normal 24-hour trough concentrations of FK506 are 33%-50% less than that of 12-hour trough.
- Lower concentrations of FK506 than normal therapeutic range means rejection of the transplanted organ.
Keywords: TAC; FK506; Tacrolimus