Pharmacokinetics: Implications for Abusable Substances
Pharmacokinetics is the study of the movements and rates of movement of drugs within the body, as the drugs are affected by uptake, distribution, binding, elimination, and biotransformation. An understanding of the biological basis of the clinical actions of abused drugs depends, in part, on knowledge of their neurochemical and neurorecptor actions that reinforce and sustain drug use (Hall, Talbert, & Ereshefsk, 1990). The pharmacokinetic properties of abusable substances represent a second important component of the database. The discipline of pharmacokinetics applies mathematical models to understand and predict the time course of drug amounts (doses) and their concentrations in various body fluids (Greenblatt, 1991, 1992; Greenblatt & Shader, 1985). Pharmacokinetic principles can be used to provide quantitative answers to questions involving the relationship of drug dosage and route of administration to the amount and time course of the drug present in systemic blood and at the receptor site of action.
Before an orally administered PSYCHOACTIVEDRUG can exert a pharmacological effect through its molecular recognition site in the brain, a number of events must take place (see Figure 1). The drug must reach the stomach and dissolve in gastric fluid. The stomach empties this solution into the proximal small bowel, which is the site of absorption of most medications.
This page contains 201 words.
Pharmacokinetics: Implications for Abusable Substances article
Read the rest of this article.
This article contains 3,833 words
(approx. 13 pages at 300 words per page).
Order our Pharmacokinetics Article
