Anti-hypertensive drugs - Calcium channel blockers

Question 1

General uses of CCBs

Answer 1

• Antihypertensives
• Class IV antiarrhythmics

Question 2

Classes, sites of action and examples

Answer 2

• Dihydropyridines
  
  • act on vascular smooth muscle
    
    • Amlodipine
    • Clevidipine
    • Nicardipine
    • Nifedipine
    • Nimodipine
• Non-dihydropyridines
  
  • act on heart (cardioselective)
    
    • Diltiazem
    • Verapamil

Memory aid:

• The pines are the dihydropyridines
• Very Nice Drugs
  
  • Verapamil
  • Nifedipine and other dihydropyridines
  • Diltiazem
• ​_V_erapamil = _V_entricle

Question 3

Why is Ca-dependent neurotransmission or hormone release not affected by CCBs?

Answer 3

CCBs block L-type Ca channels (other channels are N, P and R)

Question 4

MOA of CCBs

Answer 4

Block voltage-dependent L-type calcium channels of cardiac and smooth muscle à muscle contractility

Question 5

Potency of CCBs in vascular smooth muscle and heart

Answer 5

• Vascular smooth muscle
  
  • Amlodipine = nifedipine > diltiazem > verapamil
• Heart
  
  • verapamil > diltiazem > amlodipine = nifedipine
• Summary:*
• Diltiazem is always middle ground
• Memory aid:*
• _V_erapamil = _V_entricle

Question 6

Use of Nimodipine

Answer 6

Subarachnoid hemorrhage (prevents cerebral vasospasm)

Question 7

Use of dihydropyridines (except nimodipine)

Answer 7

• Hypertension
• Angina (including Prinzmetal)
• Raynaud phenomenon

Question 8

Adverse effects of dihydropyridine

Answer 8

• Peripheral edema
• Tachyarrhythmia
• Flushing
• Dizziness
• Gingival hyperplasia
• Headache

Question 9

CCB used in hypertensive urgency or emergency

Answer 9

Nicardipine, clevidipine

Question 10

Use of non-dihydropyridines

Answer 10

• Hypertension
• Angina
• Atrial fibrillation/flutter

Question 11

Adverse effects of non-dihydropyridine

Answer 11

• Cardiovascular effects (HF, AV block, sinus node depression, severe LV dysfunction)
• Hyperprolactinemia
• Edema
• Constipation
• Flushing

Question 12

CCBs that cause gingival hyperplasia

Answer 12

• Nifedipine
• Verapamil

Question 13

Which calcium channel blocker is the most selective for vascular smooth muscle?

Answer 13

Nifedipine

Question 14

Which calcium channel blocker is the most cardio-selective?

Answer 14

Verapamil

Question 15

Which calcium channel blocker cannot be used as an anti-arrhythmic?

Answer 15

Nifedipine

Question 16

What are the clinical indications for the use of calcium channel blockers?

Answer 16

• Hypertension
• Angina
• Raynauds disease
• Arrhythmias (except nifedipine)
• Prinzmetals angina