Medically Reviewed by Poonam Sachdev on November 15, 2021

Azathioprine is a medication available in the form of a tablet that is used to treat immune diseases, notably multiple sclerosis. It is available under the brand name Imuran. 

What is Azathioprine?

Azathioprine is a common medication for disorders of the immune system. Research has found that this medication can lower the instances of flare-ups in people with relapsing multiple sclerosis. It also reduces the formation of new lesions. 

Currently, the FDA has not approved azathioprine for multiple sclerosis. 

Azathioprine is also used to prevent rejection in a transplant. In this case, it is used with other medications, especially in people undergoing a kidney transplant. It can also be prescribed to treat rheumatoid arthritis, a condition in which the body starts attacking its joints. 

Azathioprine belongs to the drug class called immunosuppressants. These drugs stop or decrease the activity of the immune system. 

How to Use Azathioprine?

Azathioprine is used orally since it comes as a tablet.

Your doctor will check your weight and white blood cell count to prescribe the ideal dosage of this drug. Initially, the dose is low. Your doctor will increase it gradually. Most people take it twice a day. 

Although the tablet normally comes in 50 milligrams concentration, it can be halved if necessary. In some cases, your doctor may advise you to take the tablet with food to lower the risk of abdominal symptoms and nausea. 

Although azathioprine can help control the symptoms of rheumatoid arthritis, it does not cure the disease. You may have to wait for 12 weeks to see the benefits of the medications. 

Side Effects of Azathioprine

Azathioprine can have some minor side effects, such as diarrhea, vomiting, and nausea. Some side effects are more serious, though. You should talk to your doctor right away if you experience: 

Call your doctor in case of any unusual reaction to azathioprine. 

Show Sources

RxList: "IMURAN."
MedlinePlus: "Azathioprine."
Cleveland Clinic: "Azathioprine."

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