list four principles of pharmacology that the oral health professional must understand in order to provide information on drugs effects.
knowing how the drug works
potential adverse effects
oral health education info related to drug effects
the risks of taking a drug
a drugs mechanism of action
movement of a drug through the body
potential adverse effects when the drug is taken
describe the steps a drug follows after being delievered to body cells?
drug receptor interaction
mechanism of action
list seven features of receptors
location on the cell surface or within the cell
hundreds of different receptors on a single cell
complementary fit between drug and receptor
hydrophilic or hydrophobic
only one drug molecule can occupy a receptor at one time
what types of bonds are weak and easily reversed
what type of bonds are weaker than ionic
what is the strongest type of bond and often irreversible
what is the weak attractive force between some drugs and their receptors
van der Waals forces
what are the most common type of drug-receptor complexes
ionic and hydrogen
define the roles of affinity and intrinsic activity in drug action
affinity is the attractive force that binds drugs to receptors and the intrinsic activity is the ability of an agonist to interact with a receptor and initiate a response
what is related to potency?
affinity (drugs with good affinity have greater potency)
what is the difference in the effect of a weak agonist when compared to a partial agonist?
weak agonist-more of the drug is needed to produce the desired effect of a strong agonist
partial agonist-never reaches the effect of a strong agonist no matter how much drug is gen it has the affinity bu has low intrinsic activity
describe the relationship of efficacy and the ceiling dose concept
efficacy is the maximum response produced by a drug more doses wouldn't produce more of an effect this is the ceiling dose (drug has hit the ceiling and cannot go further)
compare the ceiling dose to the threshold dose
ceiling dose is when the maximum effect of a drug is reached and more drugs would not produce greater effect
threshold dose is when the lowest dose of a drug will produce a measurable response
median effective dose- dose of drug required to produce a desired response in 50% of individuals within the same population
median lethal dose- if death is measured end point of the ED50
what is the therapeutic index?
TI is the ratio of the LD50 and the ED50, it is the margin of safety of a drug
what is the significance of a high TI
the higher the TI the safer the drug
describe the stages a drug goes through from the time of administration to the elimination of the drug (5)
distribution in the body
distribution to site of action
metabolism of drug
excretion of drug
from where in the GI tract are most drugs absorbed?
what is the most predictable ROA?
which enzyme system is the primary pathway for drug metabolism
hepatic microsomal cytochrome P450
in which organ are the most drugs excreted and what is the primary area of the organ where this occurs
define a drug's half life
time required for the plasma concentration of a drug to be decreased by 50%, it takes 4 half lives to eliminate a drug from the body
ch 2 self study review