Pharmacodynamic principles and the time course of immediate drug effects.
10.12793/tcp.2017.25.4.157
- Author:
Nick HOLFORD
1
Author Information
1. Department of Pharmacology & Clinical Pharmacology, University of Auckland, Auckland, New Zealand. n.holford@auckland.ac.nz
- Publication Type:Review
- Keywords:
emax model;
Emax;
C₅₀;
time course of drug effect;
duration of drug action
- MeSH:
Half-Life;
Plasma
- From:Translational and Clinical Pharmacology
2017;25(4):157-161
- CountryRepublic of Korea
- Language:English
-
Abstract:
This tutorial defines the principles of the concentration - effect relationship which are the basis of pharmacodynamics. The two key parameters of pharmacodynamics are the maximum response (Emax) and the concentration producing 50% of Emax (C₅₀). The time course of effect is illustrated under the assumption that drug effects are immediately related to concentration in the central compartment e.g. plasma. The related idea of duration of drug action and its relationship to dose is shown to have a simple relationship with drug half-life.
