There are several criteria that a drug must meet to be a suitable candidate for therapeutic drug monitoring (TDM) and cyclosporine fulfills these criteria: cyclosporine has a narrow therapeutic index, it exhibits the desirable pharmacological effect only within narrow ranges of concentration in the blood, too much drug leads to nephrotoxicity and too little to graft rejection; the dose response relationship is poor as cyclosporine absorption is highly variable both between and within patients. Additionally, patients with transient liver dysfunction, regardless of transplantation type, will have decreased cyclosporine clearance and increased half-life values. Immediately after transplantation surgery, oral absorption of cyclosporine, especially in liver transplant patients with T-tubes, is highly variable. Obesity does not influence cyclosporine pharmacokinetics, so doses should be based on ideal body weight for these individuals.
This topic describes: TDM of cardiovascular disease, Seizure disorders, Psychiatric conditions, and Organ transplantations.