Calcium Channel Blockers

Question 1

What is the MOA of calcium channel blockers?

Answer 1

They work by blocking calcium channels in the heart and blood vessels, reducing calcium entry into cells. Calcium is essential for muscle contraction, so blocking this causes smooth muscle relaxation and reduced heart contractility/conduction.

Question 2

What are the drugs under the CCB class?

Answer 2

Verapamil, Diltiazem, Nifedipine, Amlodipine, Felodipine, Nicardipine

Question 3

What conditions does Verapamil help treat?

Answer 3

Arrhythmias and angina

Question 4

What conditions does Diltiazem help treat?

Answer 4

HTN and rate control for a fib.

Question 5

What conditions do the “pines” help treat?

Answer 5

Preferred for HTN

Question 6

What conditions are contraindications for prescribing CCBs?

Answer 6

HF due to their negative effect on heart contractility.
Heart Block/Bradycardia
Hypotension due to them lowering BP

Question 7

What are drug-drug interactions to watch for with CCBs?

Answer 7

Digoxin because CCBs increase digoxin levels
Beta-blockers

Question 8

What are short acting CCBs?

Answer 8

Nifedipine has a quick onset and shorter duration but can cause reflex tachycardia (fast HR in response to sudden drop in BP)

Question 9

What are side effects of CCBs?

Answer 9

Hypotension
Constipation
Flushing
Peripheral edema (managed by combining them with an ACE inhibitor)
Gingival hyperplasia (overgrowth of gums)