Drug Pharmacology: Kinetics, Dynamics, and Therapeutics (Vocabulary)

A comprehensive set of vocabulary flashcards covering pharmacokinetics, pharmacodynamics, therapeutic considerations, and common drug interactions and events drawn from the notes.

Half-life (pharmacology)

Time required for the drug's plasma concentration to reduce by 50%; about five half-lives are typically needed to consider the drug cleared from the body.

Steady-state (pharmacokinetics)

When the amount of drug absorbed equals the amount eliminated, producing a stable, predictable plasma concentration during scheduled dosing.

Pharmacokinetics

The study of how the body absorbs, distributes, metabolizes, and excretes a drug.

Pharmacodynamics

The study of how drugs produce their effects, including receptor interactions and mechanisms of action.

Receptor

A cellular site where a drug binds to initiate its effect.

Drug action

The drug's interaction with a receptor site, leading to a cellular response.

Drug effect

Clinical outcomes of a drug, including onset, peak, and duration of action.

Peak (drug level)

The highest blood concentration or the time when the drug's effect is maximal.

Trough (drug level)

The lowest blood concentration before the next dose.

Affinity

Strength of binding between a drug and its receptor; higher affinity generally means a stronger effect.

Agonist

A drug that binds to a receptor and activates it to produce a response.

Antagonist

A drug that binds to a receptor but does not activate it, blocking the receptor from other drugs.

Synergistic effect

Two drugs with different mechanisms that produce a greater combined effect than the sum of their individual effects.

Additive effect

Two drugs with similar actions whose combined effect equals the sum of their separate effects.

Antagonistic effect

One drug reduces or blocks the effect of another.

Incompatibility

Certain drugs, especially IV, that can cause serious adverse reactions when mixed together; often requires separate administration.

Therapeutic index/window

The range between the effective dose and the toxic dose; a narrow window requires careful monitoring.

Maintenance therapy

Long-term treatment to maintain symptom relief or function, often at a steady state.

Prophylactic therapy

Treatment given to prevent disease or infection, such as perioperative antibiotics.

Empiric therapy

Broad-spectrum treatment started before culture results are available to cover likely pathogens.

Definitive therapy

Targeted therapy chosen after culture and sensitivity results identify the specific organism.

Sepsis protocol

Hospital protocol triggered by vital signs to promptly treat suspected sepsis with fluids and empiric antibiotics, with monitoring.

Adverse drug event

Any undesirable occurrence involving a medication, ranging from minor effects to life-threatening events.

Hypersensitivity vs idiosyncratic reaction

Hypersensitivity is a predictable allergic-type reaction; idiosyncratic reaction is an unpredictable, rare reaction.

Tolerance

Diminished response to a drug with repeated use, often requiring higher doses to achieve the same effect.

Physical dependence

A biological adaptation to a drug, with withdrawal symptoms upon abrupt cessation.

Psychological dependence

A craving or compulsion to continue taking a drug, often with less physical withdrawal.

Narrow therapeutic index

A small margin between therapeutic and toxic effects; requires close monitoring (e.g., warfarin).

Absorption

Movement of a drug from its site of administration into the bloodstream.

Distribution

Dispersion of a drug throughout body fluids and tissues after absorption.

Metabolism

Biotransformation of a drug, usually in the liver, into metabolites.

Excretion

Elimination of a drug from the body via kidneys, bile, or other routes.

Naloxone (Narcan)

Opioid receptor antagonist used to reverse opioid overdose; rapid onset and often short duration requiring potential repeat dosing.

Antihistamines

Drugs that block histamine receptors to prevent or reduce allergic reactions.

Toxicology

The study of poisons, their effects, and antidotes on the body.