The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:
allopurinol, BACTRIM, co-trimoxazole, COUMADIN, warfarin (do not suddenly stop taking azathioprine or warfarin; check with your doctor), ZYLOPRIM.
The use of angiotensin converting enzyme (ACE) inhibitors to lower blood pressure together with azathioprine has been reported to cause a severe decrease in white blood cells.
Avoid live virus vaccines, such as polio vaccines, for at least three months after stopping azathioprine. Not only might the vaccine be ineffective, but you may be more apt to have adverse reactions to the vaccine. It is very important that you not come in close contact with anyone else, such as your grandchildren, getting live virus vaccines. If you must come in contact, especially with infants, wear a mask over your mouth and nose. Let someone else change and dispose of their diapers.