Pharmacology PPT 2 Flashcards
(45 cards)
what are the 3 drug action phases
drug administration phase (pharmaceutical phase)
pharmokinetic phase
pharmacodynamic phase
describe the pharmaceutical phase
making of the drug available to the body for absorption
what is the dosage form
physical state of the drug in association with non-drug components
what is the administration form
portal of entry for the drug into the body (injectable, inhalation, etc)
in terms of dosage form what different ways can it be administered
oral (enteral) injectable aerosol/MDI suppository sublingeal
route things to consider
availability of drug desired rate of onset/duration of action safety of route local/systemic effect is desired can pt swallow stability of agent in GI fluids amount of drug needed convenience
route of administration
enteral (safest cheapest and easiest to give)
parenteral (injectable - fastest and most dangerous)
transdermal (patches on skin)
inhalation
topical
pharmokinetic phase
time course and deposition of a drug in the body
what is the pharmokinetic phase based on
absorption, distribution, metabolism, elimination
in terms of the pharmokinetic phase what is absorption
when given orally the drug must dissolve freeing the active agent and by aqueous or lipid diffusion it must cross the through the epithelial lining of the stomach and enter the vascular system
in terms of pharmokinetic phase what is distribution
process by which a drug is transported to its sites of actions, eliminated, or stored. when given intravenously the drugs rush to the organs with the most blood flow then slowly disperse out
what drug is the initial distribution phase clinically important
propofol
in terms of pharmokinetic phase what is metabolism
drugs that are biotransformed and are either metabolized by the liver or the kidneys which are primarily the site for drug excretion
in terms of pharmokinetic phase what is elimination
primary site of drug excretion is the kidneys
what is clearance
measure of the ability of the body to rid itself of a drug
maintenance dose
to achieve a steady level of drug in the body, dosing must equal the rate of elimination
pharmacodynamic
refers to the interaction of the drug molecules with target receptor sites
three ways drug produce effects
key fits lock - causes reaction
key fits lock - blocks a reaction
key alters membrane permeability - allows something else to cause a reaction
lock and key
drug must reach receptor site
drug must be specific to the receptor site
drug specificity depends upon chemical structure
affinity
likeness - how often is the drug going to reach its destination
efficacy
effect - causes biological reaction
agonist
both affinity and efficacy
antagonist
drug has affinity but not efficacy
additive
2 drugs delivered at the same time and both work but they work on their own thing
1+1=2
