Modified: February 1, 2023


Dear @Name@,

Your healthcare team has discussed the following subject with you: azathioprine. Brand names include Azasan and Imuran. Here is some additional information. Let us know if you have any questions regarding this information.

How it works:This medication belongs to a class of drugs called immunomodulators. It helps to reduce irritation and swelling (inflammation) in the intestines. It also decreases the long-term need for steroids. For that reason, it is sometimes referred to as a "steroid-sparing" drug. In some cases, this medication is used by itself. In other cases, this medication is used together with another medication to achieve better results.

How it is taken: Taken as a pill typically once daily, sometimes twice daily. With this medication it can take 3 to 6 months to see an improvement of symptoms. Because it may take a while to see an improvement, they are often given along with another faster-acting medication (such as a steroid).

Common side effects: Infrequently reported side effects may include headache, nausea, vomiting, diarrhea, tiredness, mouth sores, rash, fever, joint pain, and liver inflammation.

Special considerations:  Less common side effects include inflammation of the pancreas (pancreatitis), infections, lymphoma (cancer of the lymph nodes), and skin cancer. Women who are pregnant or wish to become pregnant should talk to their healthcare team before taking this medication.

Monitoring: Blood tests should be performed frequently to check for medication effects on the bone marrow and liver. Blood tests may also be performed to check levels of azathioprine metabolites. Skin exams should occur regularly by a primary care provider or dermatology to rule out early skin cancer. Women who are taking this medication should continue to get regular Pap smears, as recommended by their gynecologist. 

Points to remember: Before taking this medication, let your doctor know about other medical conditions that you may have or other medications (even over-the-counter medications or complementary therapies) you may be taking.

Other tips: The best way to control your disease is by taking your medication as directed. Even when you do not have any symptoms, it is very important to continue taking your medication to prevent your disease from becoming active again. Do not alter the amount of the medication or how frequently you take it on your own. If you have any side effects or you continue to have symptoms, speak to your healthcare team immediately.

For further information, please check out or follow this link:


PDF /sites/default/files/2020-03/immunomodulators.pdf