β-Blocker Selectivity Nonselective β-Antagonists (β1 = β2) Drug Effect Clinical Applications Toxicity Propranolol, nadolol, timolol Lowers BP and HR Reduces renin secretion Decreases cardiac ouptut and increases peripheral resistance Hypertension Arrhythmias Angina pectoris Migraines Hyperthyroidism Glaucoma (timolol) Bradycardia Fatigue Worsening asthma Vivid dreams β1-Selective Antagonist (β1 > β2) Drug Effect Clinical Applications Toxicity Metoprolol, atenolol, betaxolol Lowers BP and HR Reduces renin secretion Hypertension Arrhythmias Angina pectoris Same toxicity as nonselective ß-antagonists but safer in asthma Esmolol Very rapid onset of action (10 min half-life) Rapid control of supraventricular arrhythmias, BP, and thyrotoxicosis Bradycardia Hypotension Nonselective α- and β-Antagonists (β1 = β2≥ α1 > α2) Drug Effect Clinical Applications Toxicity Labetalol, carvedilol Heart failure Fatigue Partial β-Agonists (β1 = β2 Blockade with Some β-Agonist Activity) Drug Effect Clinical Applications Toxicity Acebutolol, pindolol, carteolol Lowers HR less than the effect on BP Hypertension Arrhythmias Hypotension but less tachycardia than alpha blockers such as phentolamine Mechanism of Action for Clinical Application Mechanism of Action for Clinical Application Clinical Application Mechanism Hypertension ↓ Cardiac output ↓ Renin secretion by blocking β-receptor on JGA cells Angina pectoris ↓ O2 consumption by ↓ heart rate and contractility SVT (propranolol, esmolol) ↓ AV conduction velocity MI ↓ Mortality CHF Slows progression Glaucoma (timolol) ↓ Secretion of aqueous humor
QUESTIONS 1 of 7 1 2 3 4 5 6 7 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.PH.14.44) A 62-year-old male is rushed to the emergency department (ED) for what he believes is his second myocardial infarction (MI). His medical history is significant for severe chronic obstructive pulmonary disease (COPD) and a prior MI at the age of 58. After receiving aspirin, morphine, and face mask oxygen in the field, the patient arrives to the ED tachycardic (105 bpm), diaphoretic, and normotensive (126/86). A 12 lead electrocardiogram shows ST-elevation in I, aVL, and V5-V6. The attending physician suspects a lateral wall infarction. Which of following beta-blockers should be given to this patient and why? QID: 100847 Type & Select Correct Answer 1 Propranolol, because it is a non-selective ß-blocker 13% (19/148) 2 Metoprolol, because it is a selective ß1 > ß2 blocker 65% (96/148) 3 Atenolol, because it is a selective ß2 > ß1 blocker 6% (9/148) 4 Labetalol, because it is a selective ß1 > ß2 blocker 6% (9/148) 5 Nadolol, because it is a selective ß1 > ß2 blocker 1% (1/148) M 3 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK
All Videos (0) Pharmacology | Beta-Blockers Pharmacology - Beta-Blockers Listen Now 14:20 min 9/6/2021 46 plays 5.0 (1)