Cyclosporin is a potent immunosuppressive drug effective in combating tissue rejection following organ transplantation. However, therapeutic doses in humans can cause a number of adverse side effects including renal and hepatic dysfunction, hypertension, neurotoxicity, lymphoma, abnormal glucose homeostasis, hypertrichosis and gingival hypertrophy.
The efficacy and degree of toxicity of cyclosporin is highly variable between individuals. However, intra- and inter- individual variablility in cyclosporin absorption, distribution and clearance is so great that standard dosing protocols based on median population values are considered inappropriate and monitoring of cyclosporin levels is required.
Dosages must be individualised to maintain Ciclosporin levels within the narrow therapeutic window that exists between inadequate immunosuppression from low doses, and toxic effects resulting from over administration.
Trough samples should be taken in all instances except for C2 cyclosporine, where samples are taken 2 hours post dose.
Reference or therapeutic ranges are not reported as therapeutic target ranges are applied on an individual basis dependent upon specialty, dosing, period in treatment regime and clinical status. Further advice can be obtained from the appropriate speciality.