Class V Antiarrhythmics - Other Drugs

Question 1

Adenosine (Class, MOA, Indications)

Answer 1

[Class V]

MOA: stimulates A1 + A2 receptors (on SA/AV node + blood vessels)

[STOPS HEART FOR ~5 SEC]

Indications: Acute TX of PSVT + vasodilator

Question 2

Digoxin (Class, MOA, Indications)

Answer 2

[Class V - Cardiac Glycoside]

MOA: Inhibits Na/K ATPase –> inc. Ca –> inc. contractility –> baroreceptors –> dec. firing rate + conduction velocity

Indications: Supraventricular arrhythmias (rate control)

Question 3

Magnesium (Class, MOA, Indications)

Answer 3

[Class V]

MOA: Unknown

Indications: TX of Torsades

Question 4

Other Class V drugs:

• Isoproterenol (beta agonist)
• Dobutamine (beta agonist)
• Atropine (muscarinic antagonist)