title: Effect of food on the absorption of enteric-coated aspirin: correlation with gastric residence time.
abstract: The Heidelberg capsule is an indigestible indicator of gastrointestinal pH, which was used to evaluate the relationship between gastric residence time (GRT) and variability in aspirin absorption from enteric-coated tablets. In a crossover study, eight healthy subjects (four men and four women) received an enteric-coated aspirin (648 mg) together with a Heidelberg capsule while fasting or with food (breakfast, followed 4 hours later by lunch). Salicylic acid and salicyluric acid concentrations in plasma and urine were measured by HPLC. The mean (+/- SD) GRT was significantly delayed by food (0.8 +/- 0.5 vs. 5.9 +/- 3.3 hours; P less than 0.005). The mean (+/- SD) lag time (TL) and time to peak concentration (expressed as salicylic acid equivalents) were markedly prolonged after the fed regimen (2.7 +/- 0.8 vs. 8.9 +/- 3.7 hours [P less than 0.005] and 8.3 +/- 2.9 vs. 13.8 +/- 4.5 hours [P less than 0.025]). For the combined data from the fasting and fed evaluations, an excellent correlation existed between TL and GRT of the capsule (TL = 1.0 GRT + 1.95; n = 16; r = 0.94; P less than 0.0001). Women demonstrated greater delays in GRT and TL than did men. The delay in aspirin absorption from an enteric-coated tablet is directly related to its GRT, which is gender related and greatly affected by food.
mesh_terms: D000042:Absorption; D000328:Adult; D001241:Aspirin / Q000008:administration & dosage* / Q000378:metabolism; D004435:Eating; D005215:Fasting; D005260:Female; D005746:Gastric Emptying; D006626:Hippurates / Q000097:blood / Q000652:urine; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008297:Male; D012459:Salicylates / Q000097:blood / Q000652:urine; D020156:Salicylic Acid; D013608:Tablets, Enteric-Coated
chemical_list: D006626:Hippurates; D012459:Salicylates; D013608:Tablets, Enteric-Coated; C000693:salicylurate; D020156:Salicylic Acid; D001241:Aspirin