Key takeaways
Mesalamine DR (Lialda) and sulfasalazine (brands: Azulfidine, Azulfidine EN-tabs) are both used to treat ulcerative colitis (UC), but they have some key differences. Mesalamine DR is an aminosalicylate that works directly in the gut to reduce inflammation, while sulfasalazine is an anti-inflammatory medication that breaks down into two different chemicals that help block certain immune processes from causing inflammation. Mesalamine DR is a delay-release tablet that is taken once a day, whereas, sulfasalazine is available in various formulations, including immediate-release and delayed-release tablets, and is taken multiple times during the day. Sulfasalazine is also approved to treat rheumatoid arthritis (RA) and polyarticular juvenile rheumatoid arthritis, while mesalamine DR is only approved for treating UC. While both medications can cause stomach-related side effects like nausea and indigestion, sulfasalazine may also cause low sperm count and requires regular blood work to monitor liver, kidney, and blood health. Additionally, sulfasalazine is a sulfa drug, which means it can cause allergic reactions in people allergic to sulfa medications or salicylates such as aspirin, which is not a concern with mesalamine DR. Both medications have lower-cost generic versions available.
