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

• 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