Drugs and the Body Flashcards
Pharmacodynamics
the interaction between the chemical components of living systems and the foreign chemicals that enter those systems, how the drug effects the body
What are the four ways drugs work
1- to replace or act as substitutes for missing chemicals 2- to increase or stimulate certain cellular activities 3- to depress or slow certain cellular activities 4-to interfere with the functioning of foreign cells
Receptor sites
the specific areas on cell membranes where drugs act to cause an effect in the cell
Agonists
drugs that interact directly with receptor sites to cause the same activity that natural chemicals would cause
Competitive antagonists
drugs that react with receptor sites to block normal stimulation, producing no effect
Non-competitive antagonists
drugs that react with specific receptor sites to prevent the reaction of another chemical with a different receptor site on that cell
Pharmacokinetics
the study of absorption, distribution, metabolism, and excretion of drugs, how the body acts on the drug
Critical concentration
the amount of a drug that is needed to cause a therapeutic effect
Loading dose
a higher dose than is usually used for treatment to reach critical concentration quickly
Dynamic equilibrium
the rate of absorption, distribution, metabolism, and excretion of a drug
What determines the concentration of a drug in the body
dynamic equilibrium
Absorption
what happens to a drug from the time it is introduced to the body until it reaches circulating fluids and tissues
Distribution
the movement of a drug to the body’s tissues
What is distribution impacted by
the drug’s lipid solubility and the perfusion of the reacted tissues
Metabolism
the process by which drugs are changed into new, less active chemicals
