5-aminosalicylic acid in a slow-release preparation: bioavailability, plasma level, and excretion in humans

Gastroenterology. 1982 Nov;83(5):1062-70.


The release pattern, bioavailability, and kinetics of a 5-aminosalicylic acid tablet with sustained release were studied in humans. Six ileostomy patients received a single dose (500 mg). Eight and 48 h later, respectively, 58% and 65% of the dose was recovered in the ileostomy effluents, either as 5-aminosalicylic acid still retained in the preparation, free 5-aminosalicylic acid or acetyl-5-aminosalicylic acid. Fourteen healthy volunteers took 1500 mg of 5-aminosalicylic acid per day for 6 days and a steady state plasma acetyl-5-aminosalicylic acid concentration was reached on day 5 (1.1-2.9 microgram/ml). 5-Aminosalicylic acid was not detected in the plasma. At steady state, 40% of the 24-h dose was recovered from feces, and 53% from the urine. The sustained-release preparation studied provides sufficient amounts of 5-aminosalicylic acid to all parts of the gut and its curative effect in ulcerative colitis and Crohn's disease should be examined in controlled trials.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aminosalicylic Acids / administration & dosage
  • Aminosalicylic Acids / metabolism*
  • Biological Availability
  • Chromatography, High Pressure Liquid
  • Colitis, Ulcerative / drug therapy
  • Crohn Disease / drug therapy
  • Delayed-Action Preparations
  • Female
  • Humans
  • Ileostomy
  • Intestinal Absorption
  • Kinetics
  • Male
  • Mesalamine


  • Aminosalicylic Acids
  • Delayed-Action Preparations
  • Mesalamine