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Pharmacology ` PHARMACOLOGY—AUTONOMIC dRUGS Pharmacology ` PHARMACOLOGY—AUTONOMIC dRUGS SEcTIoN II 245
β-blockers Acebutolol, atenolol, betaxolol, bisoprolol, carvedilol, esmolol, labetalol, metoprolol, nadolol,
nebivolol, pindolol, propranolol, timolol.
APPLICATION ACTIONS NOTES/EXAMPLES
Angina pectoris heart rate and contractility O 2
consumption
Glaucoma production of aqueous humor Timolol
Heart failure mortality Bisoprolol, Carvedilol, Metoprolol (β-blockers
Curb Mortality)
Hypertension cardiac output, renin secretion (due to β 1 -
receptor blockade on JG cells)
Hyperthyroidism/ Symptom control ( heart rate, tremor) Propranolol
thyroid storm
Hypertrophic heart rate filling time, relieving
cardiomyopathy obstruction
Myocardial infarction O 2 demand (short-term), mortality (long-
term)
Supraventricular AV conduction velocity (class II Metoprolol, esmolol
tachycardia antiarrhythmic)
Variceal bleeding hepatic venous pressure gradient and portal Nadolol, propranolol, carvedilol
hypertension (prophylactic use)
AdVERSE EFFECTS Erectile dysfunction, cardiovascular Use of β-blockers for acute cocaine-associated
(bradycardia, AV block, HF), CNS (seizures, chest pain remains controversial due to
sleep alterations), dyslipidemia (metoprolol), unsubstantiated concern for unopposed
and asthma/COPD exacerbations α-adrenergic stimulation
SELECTIVITY β 1 -selective antagonists (β 1 > β 2 )—acebutolol Selective antagonists mostly go from A to M (β 1
(partial agonist), atenolol, betaxolol, bisoprolol, with 1st half of alphabet)
esmolol, metoprolol
Nonselective antagonists (β 1 = β 2 )—nadolol, NonZelective antagonists mostly go from N to Z
pindolol (partial agonist), propranolol, timolol (β 2 with 2nd half of alphabet)
Nonselective α- and β-antagonists—carvedilol, Nonselective α- and β-antagonists have modified
labetalol suffixes (instead of “-olol”)
Nebivolol combines cardiac-selective Nebivolol increases NO
β 1 -adrenergic blockade with stimulation of
β 3 -receptors (activate nitric oxide synthase in
the vasculature and SVR)
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