Medicine use in transplant recipients

Date Updated: 02/20/2025

After an organ transplant, antirejection medicines are used to prevent the body from rejecting the new organ. These medicines work by lowering the body's immune response, called immunosuppression. With these medicines, the immune system is weakened enough to not reject the organ but still gives enough immunity to prevent severe infections.

Antirejection medicines work in three phases to reduce side effects and suppress the immune system. The three phases are induction, maintenance, and antirejection:

Induction medicines are given in a vein before and after the transplant. Induction medicines help get the body ready to accept the transplanted organ.
Maintenance medicines are taken for as long as you have a transplanted organ. They are used long-term to continue suppression of the immune system. You often take a combination of medicines after an organ transplant. These medicines are started shortly after surgery.
Rejection treatments are medicines that are used if the body starts to reject the transplanted organ. Report any symptoms of rejection to a healthcare professional right away.

Side effects

Antirejection medicines may have side effects. They are usually manageable and get better over time. Common side effects of antirejection medicines include:

Diabetes.
High blood pressure.
High cholesterol.
Increased risk of infection.
Increased risk of some forms of cancer.
Stomach issues.

Regular blood tests are needed to check the amounts of medicine in the blood. Higher amounts of medicine in the blood can make side effects worse. If there isn't enough medicine, your transplanted organ may not have enough protection.

Antirejection medicines

Common medicines given after organ transplantation include azathioprine (Azasan), basiliximab (Simulect), belatacept (Nulojix), cyclosporine (Neoral, Sandimmune, others), muromonab-CD3 (Orthoclone OKT 3), mycophenolic acid (Myfortic), mycophenolate mofetil (Cellcept), prednisone, sirolimus (Rapamune) and tacrolimus (Prograf, Astagraf XL).

Azathioprine

Azathioprine works by reducing inflammation and stopping the production of blood-forming cells which helps prevent rejection. It is typically used with other medicines after a kidney transplant. However, it also can be used to treat severe rheumatoid arthritis and ulcerative colitis. Azathioprine comes as a tablet taken by mouth.

Side effects of azathioprine are not common, but they can happen. Effects to look for include cold hands and feet, loose stools, joint pain, loss of appetite, upset stomach, and vomiting. Contact your healthcare professional if you experience these symptoms and they don't go away.

Basiliximab

Basiliximab works by stopping the production and activation of cells that create antibodies. This helps prevent rejection. It is typically used with other medicines after a kidney transplant. Basiliximab is given as a shot by a healthcare professional.

Side effects of basiliximab may include acne, constipation, upset stomach, loose stools, headache, heartburn, trouble sleeping, weight gain, excessive hair growth, and joint and muscle pain. Contact your healthcare professional if these symptoms become severe.

Belatacept

Belatacept works by decreasing the activity of the immune system to prevent it from attacking the transplanted organ. This medicine is typically used with others after a kidney transplant. Belatacept is given as a shot by a healthcare professional.

Common side effects of belatacept include constipation, feeling very tired, fast heartbeat, headache, muscle weakness, changes in skin color, and swelling of the hands, feet, ankles or lower legs. Contact your healthcare professional if these symptoms become severe.

Cyclosporine

Cyclosporine works by stopping the production of certain cells. This helps prevent rejection. Cyclosporine is typically used in people who receive kidney, liver and heart transplants. It also can be used to treat severe psoriasis and rheumatoid arthritis. Cyclosporine comes as a capsule taken by mouth or can be given as a shot by a healthcare professional.

Side effects of cyclosporine are common. They may include breast enlargement, loose stools, increased hair growth, loss of appetite, sinusitis, upset stomach, vomiting, and tender, swollen and bleeding gums. Contact your healthcare professional if these symptoms become severe.

Muromonab-CD3

Muromonab-CD3 works by preventing certain types of white blood cells from multiplying. Muromonab-CD3 is given as a shot by a healthcare professional.

Common side effects of muromonab-CD3 include black, tarry stools, blood in urine or stools, confusion, cough, loose stools, dizziness, fever and chills, hallucinations, headache, muscle and joint pain, upset stomach and vomiting, seizures, skin rash, and more. Contact your healthcare professional if these symptoms become severe.

Mycophenolic acid

Mycophenolic acid works by preventing certain types of white blood cells from multiplying. It is often used with other immunosuppressant medicines. Mycophenolic acid comes as a tablet taken by mouth.

Common side effects of mycophenolic acid include constipation, loose stools, upset stomach, urinary tract infection and upper respiratory infection. Contact your healthcare professional if these symptoms become severe.

Mycophenolate mofetil

Mycophenolate mofetil works by preventing certain types of white blood cells from multiplying. It is often used with other immunosuppressants. Mycophenolate mofetil comes as a capsule taken by mouth or can be given as a shot by a healthcare professional.

Common side effects of mycophenolate mofetil include constipation, loose stools, headache, heartburn, nausea, stomach pain, vomiting, weakness, acne, dizziness, skin rash and trouble sleeping. Contact your healthcare professional if these symptoms become severe.

Prednisone

Prednisone is a medicine that lowers inflammation and immune system activity, called a corticosteroid. It is often used with other immunosuppressant medicines. It also can be used to treat certain forms of arthritis, severe allergies, lupus, asthma and other conditions. Prednisone comes as a tablet taken by mouth.

Side effects of prednisone are not common, but they can happen. Side effects may include acne, anxiety, depression, dizziness, bruising easily, headache, increased hair growth, restlessness and trouble sleeping, puffiness in the face, and upset stomach and vomiting. Contact your healthcare professional if these symptoms become severe.

Sirolimus

Sirolimus works by preventing certain types of white blood cells from multiplying. Sirolimus is often used with other immunosuppressant medicines. Sirolimus comes as a tablet or liquid taken by mouth.

Common side effects of sirolimus may include back pain, trouble sleeping, fever, headache, joint pain, rash, constipation, loose stools, vomiting, tremor, weakness, weight gain, and swelling of the hands, feet, ankles or lower legs. Contact your healthcare professional if these symptoms become severe.

Tacrolimus

Tacrolimus works by stopping the production of certain cells which helps prevent rejection. Tacrolimus is typically used in people who receive kidney, liver, pancreas, lung or heart transplants. It is often used with other immunosuppressant medicines. Tacrolimus comes as a tablet taken by mouth or can be given as a shot by a healthcare professional.

While side effects of tacrolimus aren't common, they can happen. Side effects may include loose stools, loss of appetite, trouble sleeping, stomach pain, upset stomach and vomiting. Contact your healthcare professional if these symptoms become severe.

Serious side effects

People who take antirejection medicines are more likely to get infections and any infections may be worse than usual. Contact your healthcare professional right away if you have any severe side effects or signs of infection, including:

Blood in the urine.
Bloody or tarry stools.
Chest pain.
Chills.
A change in color of the skin or eyes.
Fast heartbeat.
Fever.
Mouth sores.
Shortness of breath.
Skin rash.
Sore throat.
Stomach or back pain.
Tender or enlarged gums.
Unusual bleeding or bruising.
Vision changes.
Vomiting.
White patches in the mouth or throat or on the tongue.

Things to avoid while on antirejection medicines

Some things can have a harmful interaction with antirejection medicines. So you should avoid these things after an organ transplant. They include:

Certain antibiotics, medicines and supplements. Avoid some antibiotics, including erythromycin and clarithromycin, after an organ transplant. They can interact with the antirejection medicines and cause problems. Some pain medicines, including ibuprofen (Advil, Motrin IB, others) and aspirin, also should be avoided. Ibuprofen can cause upset stomach and water retention after an organ transplant. Aspirin is OK in small doses, but higher doses can cause stomach irritation and ulcers. Some supplements, including St. John's wort, may interact with antirejection medicines and should be avoided. Don't take antibiotics, medicines or supplements without first talking with your healthcare professional.
Grapefruit and pomegranate juices. Don't drink these juices while taking antirejection medicines. The juices can affect the balance of medicine levels in the body.
Pregnancy and breastfeeding. Some antirejection medicines are not safe to take during pregnancy. They can cause pregnancy loss, fetal harm, birth defects, premature labor and harm to a nursing infant. People able to get pregnant may need to use a contraceptive before starting these medicines and while using them. Talk with your healthcare professional if you become pregnant while taking an antirejection medicine.
Sunbathing. Some antirejection medicines increase the risk of skin cancer. Avoid sunbathing, and wear sunscreen and clothing that covers you when in the sun.