ABCB1 and Decreased liver function: In conclusion, our study suggests that inflammation should be taken into account for the correct comprehension and interpretation of the tacrolimus Cmin variability observed during longitudinal TDM that occurs separately from liver dysfunction, poor observance issues or blood exams performed at the wrong time, or co-medication with drug-metabolizing enzymes (cytochrome P4503A4/3A5) and transporter (P-glycoprotein) inducers or inhibitors.