Pharmacokinetic model of presystemic metabolism.
A pharmacokinetic perfusion model is presented that describes the disposition of drugs that are subject to both first-pass hepatic and intestinal epithelial metabolism. Equations are developed to estimate hepatic and intestinal epithelial clearances by determining drug concentrations as a function of time in both portal and peripheral vein blood after oral and iv administration, and by determining or estimating the flow rate of blood perfusing the gastrointestinal tissues. A method that can be used, under the stated conditions, to approximate the systemic availability after oral administration of drugs subject to presystemic metabolism is also developed.
D000284:Administration, Oral; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D008954:Models, Biological; D004364:Pharmaceutical Preparations / Q000008:administration & dosage / Q000378:metabolism*
D004364:Pharmaceutical Preparations