Pharmacodynamics 2 Flashcards
(23 cards)
A new induction agent has a median effective dose of 125 mg and the median lethal dose of 1,500 mg. Calculate the therapeutic index for this drug.
12
Describe how to calculate the therapeutic index of a drug.
TI= LD50/ED50
The _______ is the dose that produces the expected clinical response in 50% of the population.
effective dose 50
The _______ is the dose that produces death in 50% of the population.
lethal dose 50 (LD50)
The therapeutic index is
a measure of drug safety
A drug with a narrow therapeutic index has a ______ margin of safety
narrow
Examples of drugs with a narrow therapeutic index include
volatile anesthetics and chemotherapy
A drug with a wide therapeutic index has a ______ margin of safety
Wide
Examples of drugs with a wide therapeutic index include
vitamin B12
Stereochemistry is the study of
the three-dimensional structure of molecules
______ is the tetrahedral bonding of carbon (carbon binding to 4 different atoms).
Chirality
________ are chiral molecules that are non-superimposable mirror images of one another.
Enantiomers
Receptors that are stereospecific may respond
differently to different enantiomers
___ and ____ enantiomers are mirror images of each other.
R & S
Examples of drugs that are R & S enantiomers include
ketamine
isoflurane
morphine
By changing the ratio of R & S enantiomers in a mixture, we can
manipulate certain side effects
________ contains two enantiomers in equal amounts.
A racemic mixture
The more chiral carbons in a molecule, the more
enantiomers that are created
The R enantiomer stands for
right hand
The S enantiomer stands for
left hand
Drugs that exist as enantiomers, often function as
2 different drugs- with different affinities for the target receptor and different side effects
How many enantiomers exist in a molecule with one chiral carbon?
two
Provide examples of racemic mixtures.
ketamine
thiopental
methohexital
isoflurane
desflurane
mepivacaine
prilocaine
bupivacaine
morphine
methadone
ibuprofen
ketorlac
