1- pharmacodynamics Flashcards
_____ is what the drug does to the body
how drugs interact with and effect biological systems
pharmacodynamics
____ is what the body does to the drug
processes of absorption, distribution, metabolism, and elimination
pharmacokinetics
the 2 aims of drug therapy are
1) maximize efficacy
2) minimize adverse effects
what 3 approaches are possible when deciding on drug therapy? which is preferred?
1) pathophysiological
2) evidence based (best option)
3) anecdotal
if you change the formulation of the drug, typically the ____ stays the same but the _____ changes
pharmacodynamic properties stay the same
pharmacokinetics may change
if you were treating gastric ulcers, what are two points in the physiologic pathway of acid production that you might choose to target?
block histamine from binding
inhibit proton pumps (ex- Omeprazole)
what are the 2 different types of drug (and toxin) targets
receptor and non receptor targets
describe signal transduction
the activation of a downstream molecular cascade by receptor activation
what is an agonist?
activates receptor
how are partial and full agonists different?
partial agonists activate the receptor, but not to its full capability
what is antagonist
prevents receptor activation
how does drug selectivity for receptors influence drug efficacy/toxicity?
refers to the concentration of the drug required to produce a response
potency
E50 is a measure of …
potency
refers to how effective a drug is at producing a response
efficacy
the magnitude of the maximal response is a measure of…
efficacy
why is it clinically important to differentiate between potency and efficacy of a drug
if a drug binds reversibly, this means the patient…..
if a drug binds irreversibly, this means…..
once binded to the receptor, it does not come off. This means new receptor will need to be made
what is the structure-activity relationship of drugs
term for the physical interaction between a drug and its target, and the effect that has on drug target activity (utilized during drug development to improve pharmacodynamics / kinetics)
what are the 8 principles of pharmacodynamics
- drugs act through molecular targets
- receptor types determine response to many drugs
- receptors can be turned on or off
- multiple mechanisms of antagonism exist
- efficacy and potency are not the same
- receptors are not static
- selectivity is important
- the body tries to maintain homeostasis
what are the 4 major types of receptors in order of fastest to slowest response upon activation
ligand gated ion channels
GPCRs
enzyme linked receptors
intracellular receptors
what do alpha1 receptors do
vasoconstrict blood vessels
what do alpha2 receptors do
vasoconstrict then vasodilate blood vessels
what do beta1 receptors do
increase cardiac output of the heart
what do beta2 receptors do
vasodilate, and bronchodilate blood vessels
what does a beta1 agonist do
increase cardiac output
what does a beta1 antagonist do
decrease cardiac output
