Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Azathioprine may cause a serious brain infection that can lead to disability or death. Call your doctor right away if you have problems with speech, thought, vision, or muscle movement. These symptoms may start gradually and get worse quickly.
Stop using azathioprine and call your doctor right away if you have any of these symptoms of lymphoma:
fever, swollen glands, body aches, night sweats, not feeling well;
pale skin, rash, easy bruising or bleeding;
cold hands and feet, feeling light-headed or short of breath;
pain in your upper stomach that may spread to your shoulder; or
feeling full after eating only a small amount, weight loss.
Also call your doctor at once if you have:
signs of infection (fever, chills, weakness, flu symptoms, sore throat, cough, pain or burning when you urinate);
severe nausea, vomiting, or diarrhea;
easy bruising, unusual bleeding;
rapid heartbeats, shortness of breath;
pale skin, cold hands and feet; or
dark urine, jaundice (yellowing of the skin or eyes).
Common side effects may include:
nausea, diarrhea, stomach pain;
hair loss; or
skin rash.
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.
 Azathioprine side effects (more detail)
