Pharmacokinetics, Pharmacodynamics, & Therapeutics

Vocabulary flashcards covering key concepts in pharmacokinetics, pharmacodynamics, routes of administration, and drug therapy principles from the lecture notes.

Pharmacokinetics (PK)

How drugs move throughout the body, encompassing absorption, distribution, metabolism, and elimination (ADME).

Pharmacodynamics (PD)

What the drug does to the body to cause an effect, involving reactions between living systems and drugs, and their actions on target cells.

Therapeutics

The study of specific drugs and their adverse effects, nursing considerations, and how drugs are used for diagnosis, treatment, prevention, cure of disease, and alleviation of symptoms.

Rights of Medication Administration

A set of guidelines including the right drug, dose, patient, assessment, route, time, reason, to refuse, documentation, patient education, and evaluation, to ensure safe drug administration.

Oral (PO) Route of Administration

A simple, convenient, and cheap route despite drawbacks like unknown exact dose due to liver metabolism, slow onset, and potential GI irritation.

Inhalation Route of Administration

A route providing rapid effects targeting the lungs, but requires the drug to be a gas or aerosol and may interfere with respiration.

Topical and Transdermal Routes of Administration

Routes that generally cause fewer systemic side effects, but may irritate skin or mucous membranes and might not be safe on abraded/damaged skin.

Intravenous (IV) Route of Administration

A route allowing rapid drug action and nearly 100% of the dose to be received, but the drug cannot be retrieved once injected, carries a higher risk of adverse reactions, and requires sterile technique.

Intramuscular (IM) Route of Administration

A route offering rapid drug absorption, though only a small amount of drug can be given, it can be painful, and should be avoided if the patient is taking anticoagulants.

Subcutaneous (Sub-Q) Route of Administration

A less painful route for administration, but only a small amount can be given, absorption is slower, and it can irritate the skin.

PICC (Peripherally Inserted Central Catheter)

A catheter inserted in a peripheral vein that extends to a central vein, reducing the need for repeat needle sticks and allowing for longer use and less irritation, but is more invasive with risks of infection and clot formation.

ADME

An acronym representing the four processes of pharmacokinetics: Absorption, Distribution, Metabolism, and Elimination.

Absorption (PK)

The pharmacokinetic process from the time a drug enters the body until it enters the bloodstream circulation, affected by factors like dosage form, bioavailability, and route of administration.

Distribution (PK)

The pharmacokinetic process where a drug, once in the bloodstream, is carried to its sites of action, metabolism, and excretion, affected by protein binding and barriers like the blood-brain barrier.

Bioavailability

The portion of a drug dose that reaches the systemic circulation and is available to act on body cells, with IV administration being practically 100%.

Drug Potency

Also known as drug strength, it refers to the different doses of two drugs needed to produce the same pharmacological effect, or the amount of drug needed for a certain response.

Metabolism (PK)

The pharmacokinetic process where active drugs are changed into inactive metabolites, primarily occurring in the liver through enzymes like Cytochrome P-450 (CYP).

Prodrugs

Drugs that are inactive in their administered form and must be metabolized to an active form within the body to exert their effects, such as clopidogrel (Plavix).

First-Pass Effect

The initial metabolism of some oral drugs as they are carried from the intestine to the liver by the portal circulatory system before reaching systemic circulation, leading to a reduction in the available drug.

Cytochrome P-450 (CYP) Enzymes

A family of enzymes primarily located in the liver that are responsible for most drug metabolism, with CYP1, CYP2, and CYP3 members being key players.

CYP Inhibitors

Substances that reduce the activity of Cytochrome P-450 enzymes, leading to increased plasma drug levels and a higher risk of toxicity.

CYP Inducers

Substances that increase the activity of Cytochrome P-450 enzymes, leading to lower plasma drug levels and potentially decreased therapeutic effects.

Elimination (PK) / Excretion

The pharmacokinetic process of removing a drug from the body, primarily through the kidneys via urine and through feces, measured by Creatinine Clearance and Glomerular Filtration Rate.

Creatinine Clearance (CrCl) and Glomerular Filtration Rate (GFR)

Important measures of renal function, indicating the body's ability to get rid of waste products like creatinine.

Serum Drug Level

A laboratory measurement indicating the exact amount of a drug present in the blood at a particular time, reflecting the drug's lifespan after administration.

Serum Half-Life

The time required for the serum concentration of a drug to decrease by 50%, primarily determined by its metabolism and excretion rates.

Steady State

The point reached after approximately 4-5 half-lives of consistent dosing, where the amount of drug eliminated equals the amount administered, resulting in maximum therapeutic effects.

Maintenance Dose

The regular dose of a drug needed to maintain a consistent or steady-state serum drug level over time.

Loading Dose

A larger initial dose of a medication, given to rapidly attain a therapeutic blood level and achieve desired effects sooner.

Passive Diffusion

The movement of a drug from an area of high concentration to an area of lower concentration across a cell membrane, without requiring cellular energy (ATP).

Facilitated Diffusion

A process similar to passive diffusion, but involving a carrier substance (like an enzyme or protein) to move the drug across a cell membrane, without requiring cellular energy (ATP).

Active Transport

The movement of a drug from an area of low concentration to an area of high concentration across a cell membrane, requiring a special carrier and cellular energy (ATP).

Agonists

Drugs that produce effects similar to those produced by naturally occurring hormones, neurotransmitters, and other substances by occupying and activating receptor sites.

Antagonists

Drugs that inhibit cell function by occupying receptor sites and preventing natural substances and/or other drugs from reaching or activating those receptor sites.