Metabolism
The products of the azoreduction of this compound, 5-aminosalicylic acid and 4-aminobenzoyl-ß-alanine, and their N-acetylated metabolites have been identified in plasma, urine and feces.
Elimination
Less than 1% of an oral dose was recovered as parent compound 5-aminosalicylic acid or 4-aminobenzoyl-ß-alanine in the urine of healthy subjects after single and multiple doses of COLAZAL™, while up to 25% of the dose was recovered as the N-acetylated metabolites. In a study with 10 healthy volunteers, 65% of a single 2.25 gram dose of COLAZAL™ was recovered as 5-aminosalicylic acid, 4-aminobenzoyl-ß-alanine, and the N-acetylated metabolites in feces, while < 1% of the dose was recovered as parent compound.
In a study that examined the disposition of balsalazide in patients who were taking 3-6 grams of COLAZAL daily for more than one year and who were in remission from ulcerative colitis, less than 1% of an oral dose was recovered as intact balsalazide in the urine. Less than 4% of the dose was recovered as 5-aminosalicylic acid, while virtually no 4-aminobenzoyl-ß-alanine was detected in urine. The urinary recovery of the N-acetylated metabolites comprised 20-25% of the balsalazide dose. No fecal recovery studies were performed in this population.
Special Populations
Geriatric: No information is available for the geriatric population.
Pediatric: The safety and effectiveness of balsalazide in the pediatric population have not been established.
Gender: No adequate and well-controlled studies which examine balsalazide in males versus females are available. Renal Insufficiency: No adequate and well-controlled studies which examine balsalazide disposition in patients with mild, moderate, and severe renal impairment are available. Hepatic Insufficiency: No information is available for patients with hepatic impairment.
Race: No information is available which examines balsalazide in different races.
Pharmacodynamic/Pharmacokinetic Relationship
No information is available.
Drug-Drug Interactions
Neither in vitro nor in vivo drug-drug interaction studies have been performed with balsalazide.