Pharmacokinetics of 5-aminosalicylic acid from controlled-release capsules in man

✍ Scribed by D. K. Yu; B. Morrill; L. S. Eichmeier; D. H. Giesing; S. J. Weir; R. C. Lanman; M. B. Lanman

• Publisher: Springer
• Year: 1995
• Tongue: English
• Weight: 546 KB
• Volume: 48-48
• Category: Article
• ISSN: 0031-6970
• DOI: 10.1007/bf00198311

✦ Synopsis

One gram single dose of Pentasa controlledrelease 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 gg' m1-1 and 1.33 gg. m1-1 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.