Verapamil

Question 1

What class of drug is Verapamil?

Answer 1

Class IV, non-dihydropyridine CCB

Question 2

What is the common indication for Verapamil?

Answer 2

• Control ventricular during supra ventricular tachycardia
• Cardiovert supraventricular tachycardias (if re-entry around AVN)
• hypertension

Question 3

What is the mechanism of action of Verapamil?

Answer 3

Blocks calcium channels in the cardiac myocytes, SAN and AVN - slows conduction through AVN, increases the refractory period in AVN and increases the slope of phase 4 in SAN to slow HR

Increases PR and can increase or decrease HR dependent on baroreflex

Question 4

What are the common adverse reactions of Verapamil?

Answer 4

• Can lead to hypotension, decreased CO and sick sinus (when SAN can’t create correct HR for bodies needs)
• GI problems - constipation

Question 5

What are the common drug-drug interactions of Verapamil?

Answer 5

• Caution with beta-blockers due to asystole risk