Flashcards in Class 1 - Introduction to Basic Pharmacokinetics Deck (40):
What are the 6 P's Dr. Mosley wanted us to remember?
Punctual, Practice, Participate, Professional, Prepared, and Problems. (We probably don't need to know this)
What does pharmaceutics involve?
Dosage form, dosage form in stomach, drug in solution.
What does pharmacokinetics involve?
Drug in extracellular fluids and in tissues. Distribution, Metabolism, Excretion.
What is Pharmacokinetics?
Absorption, Distribution, Metabolism, and Excretion.
What is absorption?
Passage of drug molecules from the administration site into circulation.
What is distribution?
Process of reversible transfer of a drug to and from the site of measurement (to and from tissues)
What is Metabolism?
Conversion of one chemical species to another (biotransformation) body alters drug
What is excretion?
Removal of intact drug from body (Ke)
What is elimination?
Irreversible loss of drug from the body by all routes of elimination.
What is disposition?
All the kinetic processes that occur to a drug subsequent to its systemic absorption - distribution and elimination.
What is first-pass effect?
rapid metabolism of an orally administered drug before reaching the general circulation.
What is bioavailability?
Measure of the systemic availability of a drug, how much is getting into the system.
What is biopharmaceutics?
The interrelationship of the physic-chemical drug properties, dosage form and route of administration on the RATE and EXTENT of systemic drug absorption.
What is clinical pharmacokinetics?
The application of basic pharmacokinetic methods to drug therapy. Response over time for specific patients and/or drugs.
What is pharmacodynamics?
The relationship between drug concentration at the site of action and pharmacological response.
What is clinical toxicology?
Study of adverse effects of drugs in the body.
What is toxicokinetics?
The application of pharmacokinetic principles to drug safety evaluation studies.
What determines the type of blood component you use to test concentration?
Protein binding of a drug.
What are the types of blood components?
Whole blood, serum, and plasma.
How is whole blood obtained and what are its components?
Generally obtained by venous puncture and contains an anticoagulant such as heparin or ETA.
Components - All the cellular and protein elements of blood.
How is serum obtained and what are its components?
Obtained from whole blood after the blood is allowed to clot and the clot is removed.
Components - does not contain the cellular elements, fibrinogen, or the other clotting factors from the blood.
How is plasma obtained and what are its components?
Liquid supernatant obtained after centrifugation of non-clotted whole blood that contains an anticoagulant.
Components - the noncellular liquid fraction of whole blood and contains all the proteins including albumin.
What are the applications of pharmacokinetics drug modeling?
Tor relate temporal patterns of response (efficacy, harm) to drug administration following acute and chronic dosing.
To help provide a rational basis for drug design, drug selection and dosage regimen design.
To help quantitatively evaluate drug product performance in vivo and establish appropriate in vitro dissolution protocols.
To provide a means for rationally initiating and individualizing drug administration in patients.
Predict drug levels
Estimate possible accumulation of drugs and/or metabolites.
Correlate drug concentrations with pharmacologic or toxicologic activity.
Evaluate differences in the rate or extent of availability between formulations.
Describe how changes in physiology or disease affect the absorption, distribution, or elimination of the drug.
Explain drug interactions.
What are the two pharmacokinetic compartment models?
Mammillary Model(used most often) and Catenary model.
What assumption does the pharmacokinetic compartment models make?
The assumption that the central compartment treats the drug uniformly. Additionally compartments are peripheral (like drugs that have an affinity for fat or other tissues).
What does modeling do?
Helps to make pharmacokinetic predictions.
What are several closely related disciplines to pharmacokinetics?
Biopharmaceutics, clinical toxicology, toxicokinetics, and pharmacodynamics.
How is concentration related to rate in Zero-Order Reactions?
Amount of concentration of drug decreases at a constant rate.
What is the elimination rate constant for a Zero-Order reaction?
dA/dt = -k
A = -kt + A0
Most reactions are first-order reactions. T/F
How is concentration related to rate in 1st Order Reactions?
Amount or concentration of drug decreases at a rate that is proportional to the amount of drug remaining.
What is the elimination rate constant for a First-Order Reactions?
dA/dt = -kA
A = A0e^(-kt)
What is half-life?
The time required for the amount or concentration of a drug to decrease by one-half/
What is the half life for a zero-order reaction?
t1/2 = A0/2k
What is the half life for a first-order reaction?
t1/2 = 0.693/k
Is a zero order reaction half-life independent or dependent on concentration?
Depends on concentration.
Is a first order reaction half-life independent or dependent on concentration?
Independent of concentration.
What is AUC used to determine?
The effectiveness of a given drug after administration by a particular route.
What is F in the equation F = AUCoral/AUCiv?
The fraction of oral dose that enters the plasma.