Sulfasalazine was introduced in the 1920s for the treatment of rheumatoid arthritis. Studies later found the drug to be most effective in treating Ulcerative Colitis. Eventually it became the most commonly prescribed drug in the treatment of Inflammatory Bowel Disease, and it is also used in treating Crohn's disease. The drug is especially effective in the continued remission of Ulcerative Colitis.
Sulfasalazine discolors the patient's urine to a dark yellow. Side effects can include: headache, nausea, and loss of appetite. There are also instances of heartburn, indigestion, fever, and rash. The most serious but least likely problems are inflammation of colitis, hepatitis, prancreatitis, pneumonitis, and pericarditis.
The actual reason for the effectiveness of sulfasalazine is not fully understood.