calcium channel blockers - Sheet1 Flashcards
What are the two main types of calcium channel blockers?
Dihydropyridines and Non-dihydropyridines.
What is the common suffix for dihydropyridines?
-dipine (e.g., nifedipine, amlodipine).
Name two nondihydropyridine CCBs.
Verapamil and Diltiazem.
What do CCBs block to exert their effects?
Calcium (Ca2+) channels.
Where do dihydropyridine CCBs mainly act?
Blood vessels – causing vasodilation of peripheral arterioles and arteries/arterioles of the heart.
What are the therapeutic uses of dihydropyridine CCBs?
Angina pectoris and hypertension (HTN).
Why are CCBs effective for angina?
They cause vasodilation, increasing oxygen delivery to the heart muscle.
What additional effects do nondihydropyridine CCBs have compared to dihydropyridines?
They affect the myocardium, SA node, and AV node, leading to decreased force of contraction, decreased heart rate, and slowed AV node conduction.
What are the therapeutic uses of nondihydropyridine CCBs?
Angina pectoris, hypertension, and cardiac dysrhythmias (e.g., atrial fibrillation, atrial flutter, supraventricular tachycardia - SVT).
How do nondihydropyridine CCBs help in cardiac dysrhythmias?
By decreasing heart rate and slowing conduction through the AV node.
What are the two types of calcium channel blockers (CCBs)?
Dihydropyridines (-dipine drugs) and Non-dihydropyridines (Verapamil, Diltiazem).
Name some dihydropyridine CCBs.
Nifedipine, amlodipine, felodipine, nicardipine, isradipine, nisoldipine.
What is the primary action of dihydropyridine CCBs?
Vasodilation – they “open up plumbing” and lower blood pressure.
What adverse effect can dihydropyridine CCBs cause due to reflex cardiac stimulation?
Reflex tachycardia (increased HR).
What drug class can be given with dihydropyridines to counteract reflex tachycardia?
Beta blockers (e.g., metoprolol).
What are the main adverse effects of dihydropyridine CCBs?
Reflex tachycardia, acute toxicity (affecting the heart), orthostatic hypotension, peripheral edema, gingival hyperplasia (gum overgrowth).
Why should patients on dihydropyridine CCBs practice good oral care?
To prevent gingival hyperplasia (gum overgrowth).
What are the two main non-dihydropyridine CCBs?
Verapamil and Diltiazem.
What are the primary uses of non-dihydropyridine CCBs?
Angina, hypertension, cardiac dysrhythmias (IV for dysrhythmias).
Why are non-dihydropyridine CCBs first-line for hypertension in Black patients?
They are more effective at lowering BP in this population compared to other antihypertensives.
What is the net effect of non-dihydropyridine CCBs on HR, AV conduction, and contractility?
Minimal change due to reflex cardiac stimulation balancing out cardiac conduction blockade.
What are the main adverse effects of non-dihydropyridine CCBs?
Orthostatic hypotension, peripheral edema, constipation (especially verapamil), flushing, dizziness, headache, bradycardia, AV block, decreased contractility, chronic eczematous rash in older patients, gingival hyperplasia.
Why should non-dihydropyridine CCBs be used cautiously in heart failure?
They reduce contractility, which can worsen heart failure.
What cardiac conditions contraindicate non-dihydropyridine CCB use?
Sick sinus syndrome (SSS), 2nd/3rd-degree AV block, heart failure.
What are key drug interactions with dihydropyridine CCBs?
Cimetidine, famotidine, grapefruit juice (increase toxicity).
What are key drug interactions with non-dihydropyridine CCBs?
Digoxin, beta blockers, grapefruit juice.
What are contraindications for dihydropyridine CCBs?
Acute MI, unstable angina, aortic stenosis, SSS, 2nd/3rd-degree AV block.
What are contraindications for non-dihydropyridine CCBs?
Heart block, heart failure.
