# Beta-Blockers and Calcium Channel Blockers > Beta-blockers and calcium channel blockers for NEET-PG Medicine, covering selectivity, indications, adverse effects and interactions in cardiac disease. - Canonical URL: https://prepelephant.com/topics/neet-pg/medicine/beta-blockers-and-calcium-channel-blockers - Exam / course: NEET-PG · Subject: Medicine - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-14 - Last updated: 2026-10-14 - Reference basis: KD Tripathi's Essentials of Medical Pharmacology; Goodman and Gilman's The Pharmacological Basis of Therapeutics; Harrison's Principles of Internal Medicine - How to cite: "Beta-Blockers and Calcium Channel Blockers", PrepElephant, https://prepelephant.com/topics/neet-pg/medicine/beta-blockers-and-calcium-channel-blockers ## Direct answer Beta-blockers and calcium channel blockers are drugs for hypertension, angina and arrhythmias that act on the heart and vessels through different receptors and channels. Beta-1 selective blockers such as metoprolol and bisoprolol are preferred in heart failure with reduced ejection fraction, while dihydropyridines such as amlodipine suit hypertension and angina. Non-dihydropyridines such as verapamil are avoided in heart failure with reduced ejection fraction because they depress contractility. ## What you must remember - **Selectivity:** propranolol is non-selective, metoprolol, atenolol and bisoprolol are beta-1 selective, and carvedilol and labetalol also block alpha-1 receptors. - **Beta-blocker indications:** post-myocardial infarction, heart failure with reduced ejection fraction, angina, atrial fibrillation rate control, portal hypertension (propranolol) and migraine prophylaxis. - **Beta-blocker cautions:** asthma (non-selective agents are avoided), symptomatic bradycardia, heart block and decompensated heart failure. - **Beta-blocker adverse effects:** fatigue, bradycardia, bronchospasm, masking of hypoglycaemia and rebound tachycardia on abrupt withdrawal. - **Dihydropyridines:** amlodipine, nifedipine and felodipine are vascular-selective, causing reflex tachycardia, ankle oedema and gingival hyperplasia; amlodipine is neutral in heart failure. - **Non-dihydropyridines:** verapamil and diltiazem slow atrioventricular conduction, useful in supraventricular tachycardia and rate control, and are avoided in heart failure with reduced ejection fraction. - **Interactions:** verapamil or diltiazem with a beta-blocker risks heart block, and CYP3A4 inhibitors such as clarithromycin raise amlodipine levels. ## A decision sequence for cardiac patients A 58-year-old man with stable angina and hypertension asks whether a beta-blocker or a calcium channel blocker suits him better. The choice depends on heart rate, ejection fraction, airway disease and co-medication, and the steps below set out the order. 1. **Check the heart and the airway:** assess ejection fraction, heart rate, atrioventricular conduction, and any asthma or COPD before selecting a class. 2. **Match the indication:** beta-blockers suit post-infarction patients, heart failure with reduced ejection fraction and rate control, while dihydropyridines suit hypertension and angina with normal heart function. 3. **Consider a non-dihydropyridine:** verapamil and diltiazem slow conduction and help supraventricular tachycardia and rate control, but are avoided in heart failure with reduced ejection fraction. 4. **Check interactions:** combining verapamil or diltiazem with a beta-blocker risks heart block, and co-prescribed CYP3A4 inhibitors raise dihydropyridine levels. 5. **Titrate and watch side effects:** monitor heart rate and blood pressure, expect fatigue and ankle oedema, and watch for bronchospasm and masked hypoglycaemia in diabetics. 6. **Taper rather than stop:** withdraw beta-blockers gradually over days to weeks, since sudden stopping can cause rebound tachycardia and ischaemia. ## High-yield viva angles Viva questions usually test whether the drug suits the heart's pump function and the airway. - **Trap:** giving verapamil or diltiazem in heart failure with reduced ejection fraction — **Correct:** these are negative inotropes that worsen the pump, so amlodipine or an evidence-based beta-blocker is used instead. - **Trap:** using a non-selective beta-blocker in asthma — **Correct:** blocking beta-2 receptors causes bronchospasm, so non-selective agents are avoided in asthma. - **Trap:** choosing propranolol as routine first-line therapy for uncomplicated hypertension — **Correct:** propranolol is non-selective and reserved for specific indications such as portal hypertension and migraine prophylaxis. ## Frequently asked questions ### Why are non-dihydropyridine calcium channel blockers avoided in heart failure? Verapamil and diltiazem are negative inotropes that depress myocardial contractility, which worsens heart failure with reduced ejection fraction. Amlodipine, a dihydropyridine, is neutral and can be used in heart failure. Evidence-based beta-blockers are preferred for the heart failure itself. ### Which beta-blockers are used with caution in asthma? Cardioselective beta-1 blockers such as metoprolol, bisoprolol and atenolol are used with caution in asthma, since they have less effect on beta-2 receptors in the airway. Non-selective agents such as propranolol are avoided because they can precipitate bronchospasm. Any asthma patient needs close monitoring when a beta-blocker is started. ### Why do dihydropyridines like nifedipine cause reflex tachycardia? Nifedipine causes arteriolar vasodilation that lowers blood pressure, and the baroreflex responds with a rise in heart rate. Amlodipine has a slower onset and is less likely to cause this. Ankle oedema is a separate, dose-related effect of dihydropyridines. ### Why are verapamil and diltiazem dangerous when combined with beta-blockers? Verapamil and diltiazem slow atrioventricular conduction, and beta-blockers add further nodal depression. The combination can cause severe bradycardia or heart block in susceptible patients. Combined use requires careful monitoring or should be avoided.