Cyclosporine Test

It is necessary to monitor the levels of cyclosporine to maintain a healthy concentration of this drug in the blood and prevent toxicity. This is called therapeutic drug monitoring. Testing cyclosporine levels helps your doctor to adjust the dosage as required. If the levels are too low, there may be a rejection of the organ - in transplant patients - or no relief from symptoms - in autoimmune disease patients. In such cases, doctors usually increase cyclosporin dose. If the levels are high, the dose will be reduced, as excess cyclosporine can cause toxic side effects. 

See your doctor at the earliest, if you experience any of the signs listed below:

• Insomnia (difficulty falling asleep or staying asleep)
• Tremors
• Headache
• Any unusual rash, bruising or bleeding
• Mood or behavioural changes
• Inability to control body movements

You don’t need to fast before the test. Inform your doctor if you are taking any other prescription or non-prescription medicines apart from cyclosporin. This includes supplements, herbal medications and over-the-counter (OTC) medications. 

Talk to your doctor before starting any new medication while you are on cyclosporin. Many drugs do not work well with cyclosporine and other transplant medicines. You must also avoid non-prescription pain medicines and other OTC medicines unless advised by your doctor.

The test is performed just before the morning dose. Make sure that you have taken the night dose, as it determines the trough levels - the lowest blood level of a drug in the blood. Inform your doctor if you have missed the night dose as it will alter the results. 

Cyclosporine test is a routine blood test where a 5-10 mL of blood is taken from a vein in the arm. It does not take longer than two to three minutes. Your doctor or nurse will explain the steps of the test to you before withdrawing the sample. 

You may get a slight bruise at the injection site - it will fade away soon. If the bruising doesn’t go away after a few hours, please consult your doctor.

Normal results:

A normal result indicates that cyclosporine levels are within the desired range for optimum effect. It means there are better chances of graft (organ) survival in case of transplant operations and symptomatic relief in autoimmune conditions. The laboratory will provide the reference values, and your doctor will advise if any fine-tuning of the dose is required.

Abnormal results:

Abnormal results would either indicate that the cyclosporine levels are too low and the desired effect is unlikely, or that the levels are too high and you may experience the toxic symptoms stated above. If the levels are low, there are chances of organ rejection after transplantation or persistent symptoms in autoimmune diseases.

Following are the reference values for cyclosporine in nanograms per millilitre (ng/mL) and nanomoles per litre (nm/L):

• Cyclosporine levels below which optimum benefit would be unlikely – 125 ng/mL or 104 nmol/L
• Cyclosporine levels above which toxic effects may be seen – 200 ng/mL or 166 nmol/L

The therapeutic range - in which optimum benefits are seen - lies between the above two concentrations. 

Reference values may vary between different laboratories; hence, comparing results is not advised, and repeat tests should be done at the same laboratory. It is also worthwhile to understand that different individuals respond differently to the same levels of cyclosporine. Your doctor will explain precisely what your test results mean for you. 

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.