Sulphasalazine and ulcerative colitis

Sulphasalazine is metabolised by colonic bacteria and azo-reduction to produce sulpha (sulphahydrine) and salicylate moities (5-aminosalicylic acid, 5-ASA) in the colonic lumen (1)

Various points have been noted about the usefulness of sulphasalazine:

• sulphasalazine and 5-ASA have been found to be therapeutically equivalent (2)
  
  
• the efficacy of sulphasalazine is limited by substantial dose-related intolerance in addition to allergic and toxic reactions to the sulpha component
  
  
• sulphasalazine is commonly used in those patients with concomitant joint disease (2)

Reference:

• Azad Khan AK,Piris J,Truelove SC (1977). An experiment to determine the active therapeutic moiety of sulphasalazine, Lancet, 2, 892-5.
• Prescriber (2001), 12 (20), 43-58.