Class 5 Anti-arrhythmics

Question 1

What is the main drug in this class of anti-arrhythmics?

Answer 1

Digoxin

Question 2

What is digoxin used to treat?

Answer 2

Supraventricular arrhythmias (ie: supraventricular/atrial tachycardia, atrial flutter, atrial fibrillatio.) It can also be used to treat heart failure (due to DCM or degenerative valvular disease)

Question 3

How does Digoxin work?

Answer 3

Inhibition of Na+/K+/ATPase in the mycoardial cell membrane which increases Na+ available for exchange with Ca2+. The result is increase in intracellular Ca2+ which results in a positive inotropic effect.

Question 4

Digoxin ______ the sinus rate and ______ AV conduction.

Answer 4

reduces/slows

Question 5

What 2ndary effect does Digoxin have on the kidneys?

Answer 5

It acts as a diuretic mainly 2ndary to increased cardiac output.

Question 6

What are the routes that Digoxin can be given?

Answer 6

Orally or IV

Question 7

Excretion of Digoxin is mainly _____ in dogs and ______ in cats.

Answer 7

Renal/Hepatic