Key takeaways
Azathioprine (Imuran, Azasan) and sulfasalazine (Azulfidine) are both prescription medications, but they serve different purposes and belong to different drug classes. Azathioprine is an immunosuppressant used mainly to prevent kidney transplant rejection and to treat rheumatoid arthritis (RA). It works by weakening your immune system to stop it from attacking your body. On the other hand, sulfasalazine is an anti-inflammatory medication used to treat ulcerative colitis (UC) and RA. It works by breaking down into chemicals that reduce inflammation and pain. Azathioprine requires regular blood tests due to its risk of causing infections, liver damage, and certain cancers, while sulfasalazine can cause stomach issues and may lower sperm count. Both medications are available in generic forms, making them more affordable. However, sulfasalazine is also safe for children 6 years and older, unlike azathioprine.
