pharmacodynamics Flashcards
what is half life?
Amount of time med degrades 50% of it
what constitutes a long half life?
dont have to take the drug as often
what constitutes a short half life?
have to take more, maybe 5 times a day
what is an example of a drug with a short half life?
morphine or paralytic
what is an example of a drug with a long half life?
ibuprofen and Z pack (azithromycin)
what are the 3 qualities that make a drug ideal?
- effective
- safe
- selectivity (low side effects)
how do you know if a drug is more selective?
it has less side effects
what is an agonist?
promotes a receptor
example: SABAs PROMOTE bronchodilation
what is an antagonist?
blocks a receptor
what is cytochrome P450
major drug metabolizing enzyme system
they inactivate drugs or accelerate them
in some cases the metabolism can produce chemical alteration that makes the resulting molecule MORE active than the original
what is ED50
effective dose for 50% of the population
what is LD50
lethal dose for 50% of the population
what factors might effect absorption?
pH
route
surface area
blood flow
what is the difference in absorption in chew tablet and liquid medication
liquid is dissolved already, body does not have to work harder to absorb
what is drug distribution
The process by which the drug is delivered to the tissues and fluids of the body.
