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Understanding rejection

What is rejection

When you have a transplant, your immune system identifies the new organ as a foreign body and tries to reject it. This is a normal immune response.

In order to control rejection, you’ll be given a combination of medicines to suppress your immune system and stop your body from attacking its new organ. These medicines are called immunosuppresants or anti-rejection drugs and must be taken for the entire life of your graft.

After transplant it’s not unusual to experience one or more episodes of rejection during the recovery period. These can be controlled in most cases by medication.

This is a risk you will need to be aware of throughout the life of your graft. The onset of rejection does not mean your organ will be lost, but prompt treatment is critical. The symptoms of rejection depend on the type of transplant you have.


Rejection is quite common in the early stages following a transplant. It can occur any time but most commonly takes place within the first 6 months. Rejection may be mild or acute, and in most cases can be controlled if treated promptly.

Many episodes are picked up by blood tests during outpatient visits. A biopsy may be required to make a definitive diagnosis. During a biopsy a sample of the transplanted organ is collected and examined under a microscope, and the results will determine if a change in treatment is required. Doses of existing medications may increase or decrease, or a new medication may be recommended.

The dosage of immunosuppressants depends on your condition and may be very high while the tissue is being rejected. The goal of treatment is to make sure the transplanted organ or tissue works properly, and to suppress your immune system’s response.

After you no longer have signs of rejection, the dosage will likely be changed.


This information is intended for educational purposes only. Transplant Australia acknowledges that each patient experience is different and does not provide this information as a substitute for medical advice. Please contact your transplant unit or doctor if you need medical advice.

Transplant Australia gratefully acknowledges the contribution of A/P Dr Wong, Transplant Nephrologist at Westmead Hospital in reviewing this material.