03 Dose
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- 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
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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