RT Book, Section A1 Shargel, Leon A1 Wu-Pong, Susanna A1 Yu, Andrew B.C. SR Print(0) ID 56602497 T1 Chapter 7. Pharmacokinetics of Oral Absorption T2 Applied Biopharmaceutics & Pharmacokinetics, 6e YR 2012 FD 2012 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-160393-5 LK accesspharmacy.mhmedical.com/content.aspx?aid=56602497 RD 2024/11/03 AB The pharmacokinetics of drugs following intravenous drug administration are simpler to model compared to extravascular delivery (see Chapters 1–6). Extravascular delivery routes, particularly oral dosing, are important and popular means of drug administration. Unlike intravenous administration, in which the drug is injected directly into the plasma, pharmacokinetic models after extravascular drug administration must consider systemic drug absorption from the site of administration, for example, the lung, the gut, etc, into the plasma. Extravascular drug delivery is further complicated by variables at the absorption site, including possible drug degradation, metabolism, and significant inter- and intrapatient differences in the rate and extent of absorption. Absorption and metabolic variables are characterized using pharmacokinetic methods. The variability in systemic drug absorption can be minimized to some extent by proper biopharmaceutical design of the dosage form to provide predictable and reliable drug therapy (see Chapters 14–16). The major advantage of intravenous administration compared to extravascular drug absorption is that the rate and extent of systemic drug input are carefully controlled.