What is the difference between Purinethol and Imuran?

Hi, thank you for your question!

Basically, azathioprine turns into mercaptopurine in the body (mercaptopurine is an active metabolite of azathioprine). Both drugs are used for ulcerative colitis and other autoimmune conditions. There are virtually no studies that have compared one to the other directly, and from an efficacy standpoint they are equivalent if dose conversions are applied

The choice of one or the other will most often be based on the judgment and clinical experience of the physician.

I hope this has been helpful to you, and if you have any further questions, please do not hesitate to contact me!

Tom Samaha, pharmacist