Pharmacodynamics Vocabulary

Vocabulary flashcards focusing on core concepts of pharmacodynamics, drug-receptor interactions, dosing safety indices, and efficacy parameters.

Pharmacodynamics

The study of biochemical and physiologic effects of drugs, describing what drugs do to the body.

Dose Response Relationship

The concept that as you increase a drug's dose, you see an increase in physiologic response up to a maximal point.

Drug Receptors

Chemical sites in the body, located on cell surfaces or inside cells, that most drugs interact with to produce effects.

Agonist

A molecule or substance that binds to and activates a receptor, mimicking the body's own regulatory molecules.

Antagonist

A substance that prevents receptor activation by endogenous regulatory molecules or other drugs, blocking cellular activity without producing intrinsic activity.

Therapeutic Index

A measure of drug safety calculated as the ratio of the lethal dose 50 to the effective dose 50.

Lethal Dose 50

The dose of a drug or substance that is fatal in $50\%$ of people.

Effective Dose 50 ($\text{ED}_{50}$)

The average effective dose where $50\%$ of people experience a therapeutic response, used to establish standard dosing.

Narrow Therapeutic Index

A classification for drugs whose effective dose range overlaps with their lethal dose range, requiring cautious monitoring.

Maximal Efficacy

The index of the maximal response a drug can produce.

Potency

A drug characteristic referring to the dose required to produce a given effect, distinct from efficacy.