Introduction to Pharmacodynamics

These flashcards cover key concepts from pharmacodynamics, including definitions, drug action theories, dose-response relationships, and types of receptors and interactions.

Pharmacodynamics (PD) is defined as __.

The study of the biochemical and physiological effects of drugs and their mechanisms of action.

The primary focus of pharmacodynamics is __.

What the drug does to the body.

The study of how the body affects drugs is referred to as __.

Pharmacokinetics (PK).

Drug action is often mediated through __.

Receptors.

Receptor binding translates into __.

Pharmacologic effect.

The __ curve shows the relationship between drug dose and effect.

Dose-response.

Key drug properties assessed in dose-response curves include __, potency, and efficacy.

Emax.

A __ agonist is a drug that activates a receptor to produce a maximal effect.

Full.

An __ agonist binds to a receptor but produces a submaximal effect.

Partial.

An __ antagonist blocks a receptor but does not activate it.

Antagonist.

In receptor occupancy theory, __ refers to the fraction of receptors bound by a drug.

Occupancy.

Drugs that bind at sites other than the orthosteric site are called __ modulators.

Allosteric.

The intrinsic activity of a drug is also known as its __.

Efficacy.

The __ index (TI) is a measure of a drug's safety margin.

Therapeutic.

Efficacy versus __ is a key distinction in pharmacodynamics.

Potency.

The __ dose (ED50) is the dose effective in 50% of individuals.

Median effective.

In a graded dose-response curve, the x-axis represents the __.

Drug dose.

Specific binding sites for drugs on biological macromolecules are called __.

Receptors.

__ receptors are proteins that bind ligands and transduce signals.

Signal-transducing.

The effects of a drug on a biological system depend on its __ and its mechanisms of action.

Chemical actions.

The __ is a measure of the ratio between the dose causing toxic effects and therapeutic effects.

Therapeutic index (TI).

An increase in drug concentration causes a __ in receptor occupancy.

Increase.

Partial agonists function by __ both agonism and antagonism to a receptor.

Mediating.

The relationship between receptor occupancy and pharmacological response follows __ theory.

Occupancy.

Drugs acting away from the active site may either enhance or inhibit receptor function and are known as __.

Allosteric drugs.

The __ effect is defined as the maximum response a drug can produce regardless of the dose.

Emax.

A __ antagonist binds reversibly to the active site, competing with the agonist.

Competitive.

Drugs that produce effects quickly fall under the category of __ pharmacodynamics.

Fast.

The __ curve illustrates diverse responses within a population to a drug.

Quantal.

The term __ refers to drugs that enhance the effects of another drug.

Agonists.

Drugs like __ that bind to the GABA_A receptor enhance inhibitory effects.

Benzodiazepines.

Drugs that decrease activity of a target are known as __.

Inhibitors.

The __ response measures continuous drug effects in a single subject.

Graded.

Spare receptors allow for __ response even when not all receptors are activated.

Maximal.

Dose–response relationships can inform __ regimens.

Dosing.

__ effects occur with repeated use of a drug over a longer time.

Tolerance.

Rapid decreases in drug effect after repeated doses manifest as __.

Tachyphylaxis.

The term __ delineates how selectively a drug binds to its target receptor.

Selectivity.

Non-covalent (reversible) drug interactions include various types of molecular bonds like __ bonds.

Hydrogen.

Understanding __ relationships helps identify therapeutic windows for drug application.

Dose-response.

The __ of a drug's effects marks the critical point for its therapeutic application.

Maximal efficacy.

In pharmacodynamics, efficacy is characterized as the __ of a drug to produce a response.

Ability.

Drugs that outcompete natural ligands are often categorized based on their __ effects.

Antagonistic.

A dose-response curve shows how much drug is needed for a defined __.

Effect.

A __ agonist stabilizes receptor activity below baseline.

Inverse.

Understanding __ is critical for predicting drug interactions within the body.

Drug selectivity.

Receptor-mediated mechanisms form the basis of __ theory.

Binding.

Factors such as receptor can influence the pharmacodynamics of a drug.

Density.