title: Pharmacokinetics of 5-aminosalicylic acid from controlled-release capsules in man.
abstract: One gram single dose of Pentasa controlled-release capsules was administered to 24 healthy volunteers under fasting condition. Mean plasma 5-aminosalicylic acid (5-ASA) and acetyl 5-ASA concentrations peaked at 0.53 microgram.ml-1 and 1.33 micrograms.ml-1 from 3 to 4 hours following dosing, respectively. The half-lives of both compounds could not be determined as absorption of 5-ASA was continuous throughout the gastrointestinal tract. An average of 29.4% (CV: 27%) of the dose was excreted in the urine primarily as acetyl 5-ASA. Up to 91.1% of the dose was released from the capsules. Forty percent of the dose (CV: 40%) was eliminated in the feces, with 8.9% of the dose remained as formulation bounded 5-ASA, indicating that controlled-release capsules continue to release drug throughout the GI tract. 5-ASA contributed 46.7% of the salicylates eliminated in the feces and acetyl 5-ASA accounted for the balance. Controlled-release capsules produced three times more total salicylates and 10 times more total and free 5-ASA in the feces than did 5-ASA suspension. Thus, while lower systemic levels of salicylates were absorbed, greater therapeutic quantities of 5-ASA were available in the bowel.
authors.affiliation: Marion Merrell Dow Inc., Kansas City, Missouri 64137, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Yu
authors.forename: B
authors.initials: B
authors.lastname: Morrill
authors.forename: L S
authors.initials: LS
authors.lastname: Eichmeier
authors.forename: R C
authors.initials: RC
authors.lastname: Lanman
authors.forename: M B
authors.initials: MB
authors.lastname: Lanman
authors.forename: D H
authors.initials: DH
authors.lastname: Giesing
authors.forename: S J
authors.initials: SJ
authors.lastname: Weir
mesh_terms: D000328:Adult; D000636:Aminosalicylic Acids / Q000097:blood* / Q000493:pharmacokinetics* / Q000652:urine; D002214:Capsules; D016503:Drug Delivery Systems; D006801:Humans; D008297:Male; D019804:Mesalamine; D010599:Pharmacokinetics; D013997:Time Factors; D014838:Volunteers
chemical_list: D000636:Aminosalicylic Acids; D002214:Capsules; D019804:Mesalamine