CLINICAL USE
Ulcerative colitis Crohn’s disease Rheumatoid arthritis
DOSE IN NORMAL RENAL FUNCTION
Oral: 1–2 g 4 times daily, reduced to 0.5 g 4 times dailyEnema: 3 g at night Suppositories: 0.5–1 g twice daily Rheumatoid arthritis: 0.5 g daily, increased to 1.5 g twice dailyPHARMACOKINETICS
DOSE IN RENAL IMPAIRMENT
GFR (mL/MIN)
DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES
IMPORTANT DRUG INTERACTIONS
Potentially hazardous interactions with other drugsADMINISTRATION
Reconstition
–Route
Oral, rectalRate of Administration
–Comments
–OTHER INFORMATION
15% of a dose of sulfasalazine is absorbed in the small intestine and becomes highly bound to plasma proteins. The remainder is split into sulfapyridine and 5-ASA by colonic bacteria. Sulfapyridine is rapidly absorbed from the colon, whereas 5-ASA is poorly absorbedMost of a dose of sulfasalazine is excreted in the urine. Unchanged sulfasalazine accounts for 15% of the original dose, sulfapyridine and its metabolites 60%, and 5-ASA and its metabolites 20–33%
Unabsorbed drug is excreted in the faeces In patients with moderate to severe renal impairment, toxicity includes increased risk of crystalluria – ensure high fluid intake