Introduction to Biopharmaceutics & Pharmacokinetics Flashcards
active ingredients
drug
AI + excipients
drug product
interrelationship of physicochemical properties of the drug, the dosage form (drug product) in which the drug is given, and the route of administration on the rate and extent of systemic drug absorption.
biopharmaceutics
study of liberation process (release of drug from the drug product). rate & extent of systemic absorption of the therapeutically active drug. the systemic availability of the drug
bioavailability
if drug is therapeutically active, what factor?
nature of drug molecule
if drug is toxic, what factor?
Route of delivery (liberation process)
if drug has no apparent effect, what factor?
Formulation of Dosage form
The time course of drug movement in the body during absorption, distribution, metabolism, & excretion (ADME). body –> drug
pharmacokinetics
Any drug can be a poison in any dose (T/F)
T
metabolism + excretion
elimination
Harmful or undesirable effects (possible response).
toxicologic effect
Relation of the drug concentration or amount at the site of action (receptor) & its pharmacologic response. Includes biochemical and physiological effects that influence the interaction of a drug with a receptor. drug –> body.
pharmacodynamics
component of a cell or organism that interacts with a drug and initiates the chain of events leading to the drug’s observed effects
receptor
Drugs that occupy receptors and activate them.
agonist
Drugs that occupy receptors but do not activate them.
antagonist
Refers to dose and various measures of acute or integrated drug concentrations in plasma and other biological fluid.
drug exposure
Refers to direct measure of the pharmacologic effect of the drug. measurable, includes endpoints or biomarkers
drug response
Biopharmaceutics involves factors that influence:
-Design of drug product
-Stability of the drug within the drug product
-Manufacture of drug product
-Release of drug from drug product
-Rate of dissolution/release of drug from absorption site
-Delivery of drug to the site of action
scope of biopharmaceutics
- All possible effects observed following the administration of the drug in its various dosage forms
-therapeutic effect, adverse effect, drug-drug interaction - All possible effects of various dosage forms on biological response
-Onset of action, Duration of action
reflects the minimum concentration of drug needed at the receptors to produce the desired pharmacologic effect
MEC (minimum effective concentration)
represents the drug concentration needed to just barely produce a toxic effect
MTC (minimum toxic concentration)
the concentration between MTC and MEC
Therapeutic window
Mas safe yung drug na may narrow na therapeutic window (T/F)
F
ratio between toxic and therapeutic dose
Therapeutic index
corresponds to the time required for the drug to reach the MEC. drug response is observed
onset time
The ______ of the pharmacologic effect is proportional to the number of drug receptors occupied, which is reflected in the observation that higher plasma drug concentrations produce a greater pharmacologic response, up to a maximum. height of the curve
intensity
The _________ is the difference between the onset time and the time for the drug to decline back to the MEC.
duration of drug
the time of maximum drug concentration in the plasma and is a rough marker of average rate of drug absorption
time of peak plasma level
related to the dose, the rate constant for absorption, and the elimination constant of the drug
peak plasma level or maximum drug concentration
related to the amount of drug absorbed systemically. area of the curve
AUC = bioavailability
concentration of plasma/ unit time
plasma drug concentration-time curve
plasma drug conc-time curve is never linear (T/F)
T
bioavailability can be measured by AUC, conc-time curve, drug exposure, and drug response (T/F)
T
All possible physiological factors which may affect the drug contained in the dosage form (pH of the stomach & intestine, surface area of skin) (T/F)
T
A drug that is bioavailable is less likely to cause an effect in the body.
F (more likely)
Application of pharmacokinetic models to drug therapy
clinical pharmacokinetics
Factors affecting drug disposition:
Drug disposition serves as basis of dosing regimens
Disease
Age
Gender
Genetic and ethnic differences
therapeutic drug monitoring (TDM)
very potent drugs ex. w/ narrow therapeutic range; optimize efficacy and prevent adverse toxicity
drug concentrations
toxic
potentially toxic
therapeutic
potentially subtherapeutic
subtherapeutic
goal of pharmaceutic factors affecting drug bioavailability
design a drug product that will deliver active drug in the most bioavailable form
physicochemical properties
-Measurable characteristics
-Determined by the number, kind, arrangement of atoms
-Preferred expression of the properties that relate to biological action vs physical or chemical
Ex. pH, solubility, H-bonding, partition coefficient, hydrophilicity, lipophilicity, BBB, placental barrier
physicochemical factors that may alter bioavailability
- particle size of drug in solid dosage form
- particle size of dispersed phase in an emulsion
- tablet disintegration
- tablet and capsule adjuncts
- tablet coating
- crystalline drug properties
