03 Dose
peak effect of morphine higher: morphine more effecacious
peak effect at lower dose: morphine more potent
Dose-Response
quantal: if drug eliminate headache
EC50 or ED50: effective concentration or dosage. Dose needed to get 50% Emax
log of dose on X: S shaped curve, better for E50
Potency
same maximum effect
Efficacy
Competitive Antagonist
e.g. beta agonist and beta blocker at same time
beta blocker competes with beta agonist. At higher dose, beta agonist outcompete beta blocker
Emax same: how much effect beta agonist can stimulate one each receptor is same
Noncompetitive antagonist
bind to beta receptor, change its shape and make it bind agonist less
increasing dose cannot overcome effect
same thing as removing beta receptor from system
E50 same
Spare receptors
add noncompetitive antagonist, should lower Emax but shifts it right instead
reason: spare receptors activated with less potency binding
eventually with high dose noncompetitive antagonist, lower Emax, antagonize also spare receptors
Partial Agonists
increasing partial agonist dose: competitive binding
response instead of percent
clomiphene: activate estrogen receptors but not as much as estrogen
Quantal Dose
ED50: dose required for 50% pts response
lethal dose and toxic dose
higher therapeutic index: more apart LD50 and ED50, wider therapeutic window
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