title: Disposition of 5-aminosalicylic acid by 5-aminosalicylic acid-delivering compounds.
abstract: The disposition of 5-aminosalicylic acid (5-ASA) from 5-ASA-delivering drugs was studied in eight healthy volunteers. Time-related urinary excretion and faecal excretion of 5-ASA and acetyl-5-ASA were measured after a single oral dose of the azo compounds sulphasalazine and olsalazine, of the slow-release compounds Pentasa, Asacol, and Salofalk, and of plain 5-ASA. Plain 5-ASA was rapidly excreted into urine and had a low faecal recovery, indicating fast absorption proximally in the intestine and little availability to the colon. After ingestion of both azo compounds and slow-release compounds, urinary excretion of 5-ASA was markedly delayed and reduced, and faecal excretion was enhanced. At all points of time there was a significant but not very marked difference in urinary excretion of 5-ASA after ingestion of the azo compounds and the slow-release compounds, in favour of the azo compounds. A significantly larger proportion of the ingested 5-ASA, moreover, was excreted in faeces after intake of azo compounds as compared with slow-release compounds.
mesh_terms: D000328:Adult; D000636:Aminosalicylic Acids / Q000008:administration & dosage / Q000378:metabolism*; D001391:Azo Compounds / Q000008:administration & dosage*; D003692:Delayed-Action Preparations; D005243:Feces / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D019804:Mesalamine; D012460:Sulfasalazine / Q000008:administration & dosage
chemical_list: D000636:Aminosalicylic Acids; D001391:Azo Compounds; D003692:Delayed-Action Preparations; D012460:Sulfasalazine; D019804:Mesalamine; C032587:olsalazine