Sulfasalazine

Snapshot

• A 25-year-old man with a history of ulcerative colitis presents to his gastroenterologist. His ulcerative colitis had been calm but recently he developed rectal bleeding and increasingly frequent stools. A colonoscopy shows diffuse inflammatory changes localized to the rectum. He is started on topical mesalazine as well as oral sulfasalazine, which contains both an anti-inflammatory and anti-bacterial component.

Introduction

• Drugs
  • sulfasalazine
• Mechanism of action 
  • activated by gut bacteria and metabolized into sulfapyridine and 5-aminosalicylic acid (5-ASA)
  • 5-ASA
    • anti-inflammatory (COX inhibitor)
    • inhibits leukotriene synthesis and lipoxygenase
  • sulfapyridine
    • anti-bacterial
• Clinical use
  • inflammatory bowel disease
    • ulcerative colitis
    • Crohn disease
  • juvenile rheumatoid arthritis
• Adverse effects
  • gastrointestinal upset
  • drug rash
  • hemolytic anemia in those with G6PD deficiency
  • malaise
  • reversible oligospermia
  • contraindications
    • allergy to sulfa medicines
    • porphyria