azathioprine (generic name)

Azasan (brand name)

It is used to prevent organ rejection after a transplant
(ay za THYE oh preen)
Table of Contents
powered by healthline

Average Ratings

What is this medicine?

AZATHIOPRINE (ay za THYE oh preen) suppresses the immune system. It is used to prevent organ rejection after a transplant. It is also used to treat rheumatoid arthritis.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • infection
  • kidney disease
  • liver disease
  • an unusual or allergic reaction to azathioprine, other medicines, lactose, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast feeding

How should I use this medicine?

Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take your medicine more often than directed. Continue to take your medicine even if you feel better. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
  • mercaptopurine

This medicine may also interact with the following medications:

  • allopurinol
  • aminosalicylates like sulfasalazine, mesalamine, balsalazide, and olsalazine
  • leflunomide
  • medicines called ACE inhibitors like benazepril, captopril, enalapril, fosinopril, quinapril, lisinopril, ramipril, and trandolapril
  • mycophenolate
  • sulfamethoxazole; trimethoprim
  • vaccines
  • warfarin

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular checks on your progress. You will need frequent blood checks during the first few months you are receiving the medicine.

If you get a cold or other infection while receiving this medicine, call your doctor or health care professional. Do not treat yourself. The medicine may increase your risk of getting an infection.

Women should inform their doctor if they wish to become pregnant or think they might be pregnant. There is a potential for serious side effects to an unborn child. Talk to your health care professional or pharmacist for more information.

Men may have a reduced sperm count while they are taking this medicine. Talk to your health care professional for more information.

This medicine may increase your risk of getting certain kinds of cancer. Talk to your doctor about healthy lifestyle choices, important screenings, and your risk.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • fever, chills, or any other sign of infection
  • severe stomach pain
  • unusual bleeding, bruising
  • unusually weak or tired
  • vomiting
  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • hair loss
  • nausea

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 25 degrees C (59 and 77 degrees F). Protect from light. Throw away any unused medicine after the expiration date.

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.

Last Updated: March 11, 2009
Licensed from
Top of page
General Drug Tools
General Drug Tools view all tools
Tools for
Healthy Living
Tools for Healthy Living view all tools
Search Tools
Search Tools view all tools
Insurance Plan Tools
Insurance Plan Tools view all tools

What is a reference number?

When you register on this site, you are assigned a reference number. This number contains your profile information and helps UnitedHealthcare identify you when you come back to the site.

If you searched for a plan on this site in a previous session, you might already have a reference number. This number will contain any information you saved about plans and prescription drugs. To use that reference number, click on the "Change or view saved information" link below.

You can retrieve information from previous visits to this site, such as saved drug lists and Plan Selector information.