[.
]Action/Kinetics:
About one-third of the dose of sulfasalazine is absorbed from the small intestine while two-thirds passes to the colon, where it is split to 5-aminosalicylic acid and sulfapyridine. The drug does not affect the microflora.
Uses:
Ulcerative colitis. Azulfidine EN-tabs are also used to treat rheumatoid arthritis in clients who do not respond well to NSAIDs. Investigational: Ankylosing spondylitis, collagenous colitis, Crohn's disease, psoriasis, juvenile chronic arthritis, psoriatic arthritis.
Additional Contraindications
Children below 2 years. In persons with marked sulfonamide, salicylate, or related drug hypersensitivity. Intestinal or urinary obstruction.
Special Concerns:
Use with caution during lactation.
Side Effects:
Most common include anorexia, headache, N&V;, gastric distress, reversible oligospermia. Less frequently, pruritus, urticaria, fever, Heinz body anemia, hemolytic anemia, cyanosis.
Drug Interactions:
- Digoxin / Absorption of digoxin
- Folic acid / Absorption of folic acid
How Supplied:
Enteric Coated Tablet: 500 mg; Tablet: 500 mg
Dosage
•Enteric-Coated Tablets, Tablets
Ulcerative colitis.
Adults, initial: 3-4 g/day in divided doses (1-2 g/day may decrease side effects); maintenance: 500 mg q.i.d. Pediatric, over 2 years of age, initial: 40-60 mg/kg/day in 3 to 6 equally divided doses; maintenance: 30 mg/kg/day in 4 divided doses.
For desensitization to sulfasalazine.
Reinstitute at level of 50-250 mg/day; then, give double dose q 4-7 days until desired therapeutic level reached. Do not attempt in those with a history of agranulocytosis or who have experienced anaphylaxis previously with sulfasalazine.
Collagenous colitis.
2-3 g/day.
Psoriasis.
3-4 g/day.
Juvenile chronic arthritis.
50 mg/kg.
Psoriatic arthritis.
2 g/day.