Pharmacology Terminologies
Pharmacology Terminologies
Pharmacology Terminologies
Key terms
Additive effects
Drug interactions in which the effect of a combination of two or more drugs with similar
actions is equivalent to the sum of the individual effects of the same drugs given alone.
For example, 1+1=2.
Adverse effects
A general term for any undesirable effects that are a direct response to one or more
drugs.
Agonist
A drug that binds to and stimulates the activity of one or more receptors in the body.
Allergic reaction
Antagonist
A drug that binds to and inhibits the activity of one or more receptors in the body .
Antagonist are also called as inhibitors.
Antagonistic effects
Drug interactions in which the effect of a combination of two or more drugs is less than
the sum of the individual effects of the same drugs given alone (1+1=less than 2 ); it is
usually caused by an antagonizing (blocking or reducing ) effect of one drug on another.
Bioavailability
A measure of the extent of drug absorption for a given drug and route ( from 0% to
100% ) .
Biotransformation
Blood-brain barrier
The barrier system that restricts the passage of various chemicals and microscopic
entities (e.g. bacteria, viruses) between the bloodstream and the central nervous
system. It still allows for the passage of essential substances such as oxygen.
Chemical name
The name that describes the chemical composition and molecular structure of a drug.
Contraindication
Cytochrome P-450
The general name for a large class of enzymes that play a significant role in drug
metabolism and drug interactions.
Dependence
Dissolution
The process by which solid forms of drugs disintegrate in the gastrointestinal tract and
become soluble before being absorbed into the circulation.
Drug
Drug actions
The processes involved in the interaction between a drug and body cells (e.g., the action
of a drug on a receptor protein); also called mechanism of action .
Drug classification
Drug effects
The physiologic reactions of the body to a drug. They can be therapeutic or toxic and
describe how the body is affected as a whole by the drug. The terms onset, peak, and
duration are used to describe drug effects (most often referring to therapeutic effects).
Drug-induced teratogenesis
Drug interaction
Duration of action
The length of time concentration of a drug in the blood or tissues is sufficient to elicit a
response.
Enzymes
First-pass effect
The initial metabolism in the liver of a drug absorbed from the gastrointestinal tract
before the drug reaches systemic circulation through the bloodstream.
Generic name
The name given to a drug by the United States Adopted Names Council. Also called the
non-proprietary name. The generic name is much shorter and simpler than the chemical
name and is not protected by trademark.
A heredity condition in which red blood cells break down when the body is exposed to
certain drug.
Half-life
Idiosyncratic reaction
Incompatibility
The characteristic that causes two parental drugs or solutions to undergo a reaction
when mixed or given together that results in the chemical deterioration of at least one
of the drugs.
Intraarterial
Intraarticular
Intrathecal
Within a sheath (e.g. the theca of the spinal cord, as in an intrathecal injection into the
subarachnoid space).
Medication error
Any preventable adverse drug event involving inappropriate medication use by a patient
or health care professional; it may or may not cause patient harm
Metabolite
A chemical form of a drug that is the product of one or more biochemical (metabolic)
reactions involving the parent drug. Active metabolites are those that have
pharmacologic activity of their own, even if the parent drug is inactive. Inactive
metabolites lack pharmacologic activity and are simple drug waste products awaiting
excretion from the body (e.g. via the urinary, gastrointestinal, or respiratory tract)
Onset of action
The time required for a drug to elicit a therapeutic response after dosing.
Parent drug
The chemical form of a drug that is administered before it is metabolized by the bodys
biochemical reactions into its active or inactive metabolites. A parent drug thats is not
pharmacologically active itself is called a prodrug. A prodrug is then metabolized to
pharmacologically active metabolites.
Peak effect
The time required for a drug to reach its maximum therapeutic response in the body.
Pharmaceutics
The science of preparing and dispensing drugs, including dosage form design.
Pharmacodynamics
The study of the biochemical and physiologic interactions of drugs at their sites of
activity. It examines the physicochemical properties of drugs and their pharmacologic
interactions with body receptors.
Pharmacoeconomic
Pharmacogenomics
The study of the influence of genetic factors of drug response, including the nature of
genetic aberrations that result in the absence, overabundance, or insufficiency of drug-
metabolizing enzymes.
Pharmacognosy
The study of drugs that are obtained from natural plant and animal sources.
Pharmacokinetics
The study of what happens to a drug from the time it is put into the body until the
parent drug and all metabolites have left the body. Pharmacokinetics represent the drug
absorption into, distribution and metabolism within, and excretion from the body.
Pharmacology
Prodrug
Receptor
A molecular structure within or on the outer surface of a cell. Receptors bind specific
substances (e.g., drug molecules), and one or more corresponding cellular effects (drug
actions) occurs as a result of this drug- receptor interaction.
Steady state
The physiologic state in which the amount of drug removed via elimination is equal to
the amount of drug absorbed with each dose.
Substrates
Substance (e.g., drugs or natural biochemicals in the body) on which an enzyme acts.
Synergistic effects
Drug interactions in which the effect of a combination of two or more drugs with similar
actions is greater than the sum of the individual effects of the same drugs given alone.
For example, 1 + 1 is greater than 2 (compare with additive effects).
The process of measuring drug levels to identity a patients drug exposure and to allow
adjustment of dosages with the goals of maximizing therapeutic effects and minimizing
toxicity.
Therapeutic effect
Therapeutic index
Tolerance
Toxicity
Toxicology
The study of poisons, including toxic drug effects, and applicable treatments.
Trade name
The commercial name given to a drug product by its manufacturer; also called the
proprietary name.
Trough level
The lowest concentration of drug reached in the body after it falls from its peak level,
usually measured in a blood sample for therapeutic drug monitoring.