Tests for cyclosporine are used to measure the amount of this drug in the blood to determine whether cyclosporine concentrations have reached therapeutic levels and are not in a toxic range. Cyclosporine is a drug that diminishes the body’s immune response. It is prescribed for organ transplant recipients to prevent organ rejection and for some people with autoimmune conditions, such as rheumatoid arthritis, to alleviate symptoms.
Cyclosporine testing is ordered frequently at the start of therapy, often on a daily basis when trying to establish a dosing regimen. Once an appropriate dose has been determined, the level can be tested less frequently and may eventually be tested monthly, once every two months, or at longer intervals. However, testing may be done more often when a person becomes ill or begins taking additional medications that may affect the metabolism of cyclosporine. A change in a person’s metabolic status may also prompt more frequent testing.
The therapeutic range for cyclosporine depends on the method used to measure the drug, the type of transplant, and the length of time since the transplant. Results obtained from different types of samples and different methods are not interchangeable. Health practitioners will be guided by the laboratory as to the appropriate therapeutic range to apply to a specific person’s test result.
If trough levels fall below the desired range, there is a risk of transplant rejection or symptom recurrence. If levels detected are above the range, there is a risk of toxic side effects.
Peak concentrations of samples collected 2 hours post-dose are sometimes tested in transplant cases. High levels of cyclosporine in peak samples are correlated with reduced rejection rates, especially in the first year after transplant surgery.
- Sample of whole blood
- We perform the test daily