Educational Forum - Therapeutic drug monitoring of immunosuppressants: An overview

Immunosuppressant drugs have contributed significantly to the success of organ transplantation. Therapeutic drug monitoring is an integral part of transplant protocols. Immunosuppressants require therapeutic drug monitoring because of their narrow therapeutic index and significant variability in blood concentrations between individuals. The variability in blood concentrations can be because of factors like drug-nutrient interactions, gender influence and polymorphism. Drug monitoring is widely practised especially for cyclosporine, tacrolimus, sirolimus and mycophenolic acid. The accuracy and specificity of the drug measurements are fundamental to the clinical interpretation of the concentration data. The issues surrounding the measurement and interpretation of immunosuppressant drug levels such as body fluids used for drug estimation, protein binding, sampling time and method for assay of the drug are discussed in detail in the article.

Keywords
Cyclosporine, mycophenolic acid, sirolimus, tacrolimus, therapeutic drug monitoring