Pharmacology Flashcards
bioavailability
fraction of drug reaching the circulation unchanged IV=100%
Clearance
volume of cleared of drug per unit time
half life
the time used to change the amount of drug in the body in 1/2 duration time
additive
the sum of drug A and B is the same as their individual effects
Apirin and acetaminophen
permissive
presence of substance A is required to attain full of B
cortisol and catecholamine
synergystic
effect of substance A and substance B together is greater than the sum of their individual effects.
clopedogrel and aspirin
tachyphylatic
acute decrease in response to a drug after initiation
competitive antagonist
decrease potency, no change in efficacy
noncompetitive antagonist
decrease in pot. and efficacy. cannot be overcome by antagonist
partial agonist (alone)
decrease potency and efficacy, act on the same site as the full agonist
zero order elimination
rate of elimination is constant, ie constand amount of drug elimination, PEA is round:
Phenythoin, Ethanol, Aspirin
first order elimination
rate of elimination is directly proportional to drug concentration, constant fraction of elimination per unit time, most drugs
explain ph and drug elimination
ionized species are trapped in urine and cleared quickly. neutral species are reabsorbed.
weak acids
eg: phenobarbital, methotrxate, aspirin. trapped in basic enviroment. Treat overdose with sodium bacarbonate to alkalinize urine.
weak basis
eg: TCAs, amphetamines. Trapped inacidic eviroments. Treat overdose with ammonium chloride to acidify urine.
Phase 1
Reduction, Oxidation, Hydrolysis with cytochrome P450.
R-OH
Phase2
Conjugation (Methylation, Glucuronidation, Acetylation, Sulfation)
2 (too) Much GAS
efficacy
max. drug effect a drug can prodce
potency
amount of drug needed for a given effect
bethanechol
Colinomimetic , bladder smooth muscle activation, resistant to AChE; Used in urinary retention
Carbachol
Colinomimetic, carbon copy of acetylchloine, used in glaucoma
metacholine
Colinomimetic, stim. muscarinic resep.
pilocarpine
Colinomimetic, contracts ciliary muscle, use glacoma
what drugs are used in Alzheimer disease
anticholinesterase, Dona Riva, dance at a Gala
