Pharmacology Terms and Definitions

Flashcards covering key pharmacology terms and their definitions to aid in exam preparation.

Absorption

The entrance of a drug into the bloodstream from its site of administration.

Additive effects

When the combined effect of two drugs that produce the same biologic response by the same mechanism of action, is equal to the sum of their individual effects.

Adverse Effect

An undesired effect of a drug that may be harmful or with prolonged treatment may cause conditions that affect the functions of vital organs.

Agonist

Drugs that bind to a receptor and initiate an action that mimics the normal physiological function.

Antagonist

Drugs that bind to a receptor and blocks the normal physiological response.

Bioavailability

Percentage or amount of the drug that is absorbed into the bloodstream.

Carcinogen

Drugs that promote the growth of cancerous tumors.

Ceiling effect

The limit of some drug classes to produce a particular effect; increasing the dose beyond this point will not produce any further effects.

Contraindications

A situation or circumstance where a drug should NOT be used.

Controlled substance

Drugs that have a potential for abuse and are therefore regulated by law.

Distribution

Passage of a drug from the blood to the tissues and organs of the body.

Dose

A measurement of the amount of drug administered.

Drug addiction

A condition of drug abuse and dependence characterized by compulsive drug behavior.

Drug dependence

Condition of reliance on the use of a particular drug, characterized as physical and/or psychological dependence.

Drug indications

The therapeutic use or uses of any drug.

Drug microsomal metabolizing system (DMMS)

A group of enzymes primarily located in the liver that function to metabolize drugs.

Drug tolerance

Decreased drug effect occurring after repeated administration; needing to increase the dose to produce the previous effect.

Duration of action

The length of time that a drug continues to produce its effects.

Enzyme induction

Increasing the amount of drug metabolizing enzymes after repeated administration of certain drugs.

Enzyme inhibition

Inhibition of drug-metabolizing enzymes by certain drugs; slows metabolism of other drugs.

Excretion

The elimination of the drug from the body.

First-pass metabolism (first-pass effect)

Drug metabolism that occurs in the liver before the drug is distributed systemically.

Half-life

The time required for the blood or plasma concentration of a drug to fall to half of the original level.

Incompatibility

A type of drug interaction that causes physical alterations of drugs that occur before administration.

Mechanism of action

Explanation of how a drug produces its effect.

Metabolism

The chemical alteration of drugs and foreign compounds in the body into metabolites.

Onset of action

The time from drug administration to the first observable effect.

Pharmacology

The study of drugs.

Pharmacokinetics

Study of the process of drug absorption, distribution, metabolism, and excretion.

Pharmacodynamics

Study of the action of drugs on living tissue.

Pharmacogenomics

Study of how genetics affect the body’s response to a drug.

Pharmacotherapeutics

Study of the use of drugs in treating diseases.

Pharmacy

The study of preparing and dispensing drugs.

Posology

The study of the amount of drug that is required to produce therapeutic effects.

Potency

A measure of the strength or concentration of a drug required to produce a specific effect.

Receptor

Specific cellular structure that a drug binds to in order to produce a physiologic effect.

Side effect

Undesired drug effect that is more of a nuisance than harmful.

Site of action

The location within the body where the drug exerts its therapeutic effect.

Summation

When the combined effects of two drugs that produce the same biologic response by different mechanisms of actions, is equal to the sum of the individual effects.

Synergism (synergistic effects)

When the combined effect of two drugs is greater than the sum of their individual effects.

Teratogens

Drugs that produce birth defects.

Therapeutic effect

Desired drug effect to alleviate some condition or symptom of disease.

Toxic effect

Undesirable drug effect that implies drug poisoning and can be very harmful.

Toxicology

The study of harmful effects of drugs on living tissue.