Azathioprine: a guide for Young People

Azathioprine is a drug used to treat both Crohn’s Disease and Ulcerative Colitis – the two main forms of Inflammatory Bowel Disease (IBD). You may be given azathioprine if you keep getting flare-ups even though you are on other medicines for your Crohn's or Colitis, or to help you cut down on steroids. You may be also be given azathioprine soon after diagnosis if your Crohn's or Colitis is troublesome to start with. 

Azathioprine may be known by a brand name, such as ‘Imuran’. There is another drug similar to azathioprine which is prescribed by some hospitals called mercaptopurine. Mercaptopurine can sometimes be used in people who cannot tolerate azathioprine. In general, the information below can be applied just as much to mercaptopurine as azathioprine.

What does it do?
What does it look like?
How often do I take it?
Will I feel better straight away?
I've been told I need tests before I can take azathioprine. Why is that?
Will I get side effects?
8 things you can do to help keep yourself healthy while taking azathioprine
Where can I get more information if I am worried?
Help and support from Crohn's & Colitis UK
How we write our information

Last reviewed: April 2016