I. Glossary
Absorption: The first stage of pharmacokinetics where medications enter the body and travel from site of administration into the body’s circulation.
ADME: Four basic stages of pharmacokinetics a medication goes through within the human body: absorption, distribution, metabolism, and excretion.
Adverse effect: An unintended and potentially dangerous pharmacological effect that occurs when a medication is administered correctly.
Affinity: The strength of binding between drug and receptor.
Agonist: A drug that binds to a “receptor” and produces an effect.
Antagonist: A molecule that prevents the action of other molecules, often by competing for a cellular receptor; opposite of agonist.
Bioavailability: The presence of a drug in the bloodstream after it is administered.
Blood-brain barrier: A nearly impenetrable barricade that is built from a tightly woven mesh of capillaries cemented together to protect the brain from potentially dangerous substances such as poisons or viruses.
Complementary and alternative medications (CAM): Therapies that are commonly used in conjunction with, or as an alternate to traditional medical therapies, such as vitamins, herbs, and other supplements. These substances are not regulated by the FDA and most have not undergone rigorous scientific testing for safety for the public.
Distribution: The second stage of pharmacokinetics where medication is dispersed throughout the body via the bloodstream.
Dose-response: The dose of medication required to achieve the desired response to the medication.
Drugs: Medications or other substances that have a physiological effect when introduced to the body.
Duration: The length of time that a medication is producing its desired therapeutic effect.
Efficacy: The maximum effect of which the drug is capable.
Excretion: The final stage of pharmacokinetics where drug byproducts and metabolites are eliminated from the body.
First-pass effect: The inactivation of orally or enterally administered drugs in the liver and intestines.
Half-life: The rate at which 50% of a drug is eliminated from the body when it is metabolized.
Mechanism of action: How a medication works at a cellular level within the body.
Metabolism: The third stage of pharmacokinetics that involves the breakdown of a drug so that it can be excreted by the body.
Onset: When a medication first begins to work and exerts a therapeutic effect.
Peak: When the maximum concentration of a drug is in the bloodstream.
Pharmacodynamics: The effects of drugs in the body and the mechanism of their action.
Pharmacogenetics: The study of how a person’s genetic makeup affects their response to medicines.
Pharmacokinetics: The study of how the body absorbs, distributes, metabolizes, and eliminates drugs.
Pharmacology: The science dealing with actions of drugs on the body.
Pharmacy: The science of the preparation of drugs.
Potency: The drug dose required to produce a specific intensity of effect.
Selectivity: The separation between the desired and undesired effects of a drug.
Side effect: Effect of a drug, other than the desired effect, sometimes in an organ other than the target organ.
Steady state: The point at which the amount of drug entering the body is equal to the amount of drug being eliminated, resulting in a stable drug concentration.
Therapeutic index: A quantitative measurement of the relative safety of a drug that compares the amount of drug that produces a therapeutic effect versus the amount of drug that produces a toxic effect. Medication with a large therapeutic index is safer than a medication with a small therapeutic index.
Therapeutic window: The dosing window in which the safest and most effective treatment will occur.
Titration: The process of adjusting a medication dose to achieve a desired therapeutic effect for the client.
Trough: A drug level drawn from the bloodstream when the drug is at its lowest concentration, typically right before the next scheduled dose is given.