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Imuran

Generic Name: azathioprine (ay za THYE oh preen)
Brand Name: Azasan, Imuran

Medically reviewed by Drugs.com on Jul 2, 2018 – Written by Cerner Multum

What is Imuran?

See also: Entyvio

Imuran lowers your body's immune system. The immune system helps your body fight infections. The immune system can also fight or "reject" a transplanted organ such as a liver or kidney. This is because the immune system treats the new organ as an invader.

Imuran is used to prevent your body from rejecting a transplanted kidney. It is also used to treat symptoms of rheumatoid arthritis.

Imuran may also be used for purposes not listed in this medication guide.

Important Information

Some people using Imuran have developed a rare fast-growing type of lymphoma (cancer). This condition affects the liver, spleen, and bone marrow, and it can be fatal. This has occurred mainly in teenagers and young adults using this medicine or similar medicines to treat Crohn's disease or ulcerative colitis.

Before taking this medicine

You should not take Imuran if you are allergic to Imuran, or if you are pregnant (unless the benefits of treating you outweigh any risks posed by taking this medicine).

Some people using Imuran have developed a rare fast-growing type of lymphoma (cancer). This condition affects the liver, spleen, and bone marrow, and it can be fatal. This has occurred mainly in teenagers and young adults using this medicine or similar medicines to treat Crohn's disease or ulcerative colitis.

However, people with autoimmune disorders (including rheumatoid arthritis, Crohn's disease, ankylosing spondylitis, and psoriasis) may have a higher risk of lymphoma. Talk to your doctor about your individual risk.

While taking Imuran, you may have a higher risk of developing skin cancer. Talk to your doctor about this risk and what skin symptoms to watch for.

To make sure Imuran is safe for you, tell your doctor if you have:

FDA pregnancy category D. Do not use Imuran if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

Azathioprine can pass into breast milk and may harm a nursing baby. You should not breast-feed while you are using azathioprine.

This medication can affect fertility (your ability to have children), whether you are a man or a woman. Talk with your doctor if you have concerns about this.

How should I take Imuran?

Your doctor may perform blood tests to make sure you do not have conditions that would prevent you from safely using Imuran.

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Take Imuran with food to lessen stomach upset.

You may not be able to continue taking other arthritis medications together with Imuran. Follow your doctor's dosing instructions very carefully.

Imuran can lower blood cells that help your body fight infections and help your blood to clot. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. Your blood will need to be tested often.

It may take up to 8 weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.

If you need surgery, tell the surgeon ahead of time that you are using Imuran. You may need to stop using the medicine for a short time.

Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Imuran?

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Avoid exposure to sunlight or tanning beds. Imuran can increase your risk of developing skin cancer. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Do not receive a "live" vaccine while using Imuran. The vaccine may not work as well during this time, and may not fully protect you from disease. Live vaccines include measles, mumps, rubella (MMR), rotavirus, typhoid, yellow fever, varicella (chickenpox), zoster (shingles), and nasal flu (influenza) vaccine.

Imuran side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using Imuran and call your doctor right away if you have any of these symptoms of lymphoma:

  • fever, night sweats, weight loss, tiredness;

  • feeling full after eating only a small amount;

  • pain in your upper stomach that may spread to your shoulder; or

  • easy bruising or bleeding, pale skin, feeling light-headed or short of breath, rapid heart rate.

Imuran may cause a serious viral infection of the brain that can lead to disability or death. Call your doctor right away if you have any change in your mental state, decreased vision, or problems with speech or walking. These symptoms may start gradually and get worse quickly.

Also call your doctor at once if you have:

  • signs of infection (fever, chills, sore throat, body aches, weakness, muscle pain, flu symptoms);

  • severe nausea, vomiting, or diarrhea;

  • pain or burning with urination;

  • white patches or sores inside your mouth or on your lips; or

  • liver problems--nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Imuran?

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with Imuran, especially:

This list is not complete. Other drugs may interact with azathioprine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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