Effect of mycophenolic acid on inosine monophosphate dehydrogenase (IMPDH) activity in liver transplant patients

•Mycophenolic acid (MPA) is a noncompetitive inhibitor of inosine monophosphate dehydrogenase (IMPDH) and has become a part of the standard therapy after liver transplantation.•MPA levels and corresponding IMPDH activity showed a broad interindividual variability and seems to be influenced by several factors, including BMI, kidney function and concomitant medication.•While patients with higher IMPDH inhibition acquires more often CMV infections, insufficient or delayed IMPDH inhibition after MPA administration is associated with non-anastomotic bile duct strictures and reduced re-transplantation-free survival.•Measurement of MPA levels and estimation of corresponding IMPDH activity in liver transplanted patients might be as a useful instrument for monitoring individual MPA dependent immunosuppression.