Calcium Channel Blockers (Amlodipine)

Question 1

What is are calcium channel blockers used for?

Answer 1

1) Hypertension (dihydropyridines CCB)
2) Stable angina (All CCBs)
3) Supraventricular arrhythmias (Non-dihydropyridines CCB)

Question 2

Which calcium channel blocker is used to treat hypertension?

Answer 2

Amlodipine (Dihydropyridine)

Question 3

How do Calcium channel blockers work to treat hypertension?

Answer 3

Calcium channel blockers reduce calcium entry into the vascular and cardiac cells.
This reduces calcium concentration.
leads to relaxation and vasodilation of arterial smooth muscle.
thereby reducing arterial pressure.

Question 4

How do calcium channel blockers work to prevent angina?

Answer 4

CCBs reduce conduction in the AV node. 
This reduces the heart rate.
Less calcium conc leads to decreased contractibility of the heart.
Less oxygen demand of myocardiocytes.
So less angina.

Question 5

What are the side effects of amlodipine (dihydropyridine calcium channel blocker) - a vascular selective drug

Answer 5

• ankle swelling
• flushing
• headache
• palpitations

Question 6

What are the side effects of verapamil? (a cardio-selective non-dihydropyridine)

Answer 6

• constipation
• bradycardia
• heart block
• cardiac failure

Question 7

What are the side effects of diltiazem? ( a non-dihydropyridine with both cardiac and vascular function)?

Answer 7

vascular side effects:

• ankle swelling
• flushing
• headache
• palpitations

Cardiac side effects:

• bradycardia
• heart block
• cardiac failure

-constipation

Question 8

In which patients should verapamil and diltiazem be used in caution with?

Answer 8

verapamil and diltiazem should be used in caution those with poor left ventricular function

Question 9

In which patients should verapamil and diltiazem (non-dihydropyridines) be avoided in?

Answer 9

AV nodal conduction delay avoid verapamil and diltiazem as it can provoke complete heart block.

Question 10

In what patients should amlodipine and nifedipine be avoided in?

Answer 10

1) unstable angina as vasodilation causes a increase in contractibility and tachycardia thereby increasing oxygen demand.
2) Severe aortic stenosis –> provokes collapse.

Question 11

What are the drug interactions of non-dihyrdopyridine CCBs (verapamil and diltiazem)

Answer 11

DO NOT USE Non dihydropyrdine calcium channel blockers with BETA BLOCKERS can lead to:

• heart failure
• bradycardia
• asystole

Question 12

How are calcium channel blockers taken? Route

Answer 12

Amlodipine, nifedipine, diltiazem = oral
Verapamil = IV

(amlodipine taken once daily, 5-10mg)