Introduction to Pharmacodynamics

A comprehensive set of flashcards focusing on key concepts of pharmacodynamics, pharmacokinetics, receptor theories, and drug classification for students in pharmacology.

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

Pharmacodynamics (PD)

______ describes the effects of the body on drugs, including absorption, distribution, metabolism, and excretion.

Pharmacokinetics (PK)

Dose–response curves help evaluate drug and .

potency and efficacy.

Receptor Occupancy Theory describes how receptor binding translates into __.

pharmacologic effect.

The parameters EC₅₀ and Emax are used in the evaluation of __ curves.

dose-response.

A __ is a molecule that binds to a receptor and produces a biological response.

agonist.

A __ is a drug that binds to a receptor but does not produce a biological effect.

antagonist.

Full agonists produce the __ possible response.

maximum.

Partial agonists activate receptors but produce a __ response.

submaximal.

The therapeutic index (TI) is defined as the ratio between and doses.

toxic and effective.

______ is characterized by a gradual decrease in drug effect occurring over days to weeks.

Tolerance

________ is characterized by a rapid decrease in drug effect occurring within minutes to hours..

Tachyphylaxis

An agonist that binds to the active site of a receptor is classified as __.

orthosteric.

An agonist that binds and activates a receptor, but its efficacy is less than that of a full agonist is known as a __ agonist.

partial.

Drugs that increase the activity of a target are classified as __.

activators.

Drugs that decrease the activity of a target are classified as __.

inhibitors.

The __ of a drug determines its strength and clinical applicability.

potency.

Competitive antagonists shift the agonist dose-response curve __.

to the right.

Non-competitive antagonists _____ efficacy without changing the position of the agonist dose-response curve.

decrease

High selectivity for a receptor correlates with lower __ toxicity.

off-target

Differences in selectivity between drugs can be calculated using the ratio of or .

Kds or EC50s.

A drug with a ____ therapeutic index is considered safer.

high

_____ in pharmacodynamics focuses on the mechanism of drug effects.

Phase B

Receptor occupancy leads to physiological effect through ______

signal transduction

The relationship between drug dose and physiological effect is illustrated by a __ curve.

dose-response

An agonist that binds to the receptor and reduces its activity is termed an __.

inverse agonist.

The binding affinity of a drug is determined by the __ free energy change.

Gibbs.

The median effective dose (ED₅₀) is an important aspect of __ dose-response curves.

quantal.

The __ response curve illustrates continuous responses to drug dosage.

graded.

Medication adherence can be affected by __ changes over time.

tolerance.

A therapeutic window is assessed using __ dose-response curves.

quantal.

The equilibrium expression for receptor-ligand binding assumes receptor concentration is __ than drug concentration.

smaller

____ curves assess the percentage of individuals demonstrating a defined effect.

Quantal

Reversible inhibitors form __ bonds, while irreversible inhibitors form permanent bonds.

non-covalent

_____ usually occurs with short-term exposure to a drug.

Tachyphylaxis

The __ is a measure of how much drug is required to produce a given effect.

potency.

Exposure to a drug over time can result in __ changes.

adaptive.

The upper limit of a response in pharmacodynamics is termed __.

Emax.

The steepness of slope on ____ dose-response curves indicates population variability.

quantal

Receptor-binding potency is measured using the ____ _____.

dissociation constant (Kd)

______ curves give insight into a drug's overall effect in a population.

Quantal

The study of the effect of drugs on biological function is known as __.

pharmacology.

_______ activity describes the ability of a drug to elicit a response once bound to its receptor.

Intrinsic

_____ measures how effectively a drug activates its target to produce an effect.

Efficacy

Receptor occupancy theory posits a __ correlation between receptor binding and bioactivity.

direct.

An __ action is defined by the ability to block another drug's effects at a receptor.

antagonistic.

An increase in receptor activation due to concurrent ligand presence is termed __ interaction.

synergistic.

Therapeutic drugs with low TI must be managed carefully to avoid __ effects.

toxic.

Potential drug toxicity can increase if a drug has a very __ therapeutic index.

narrow.

New pharmacologically-active compounds should exhibit desirable __ selectivity in drug formulation.

target.