Amiodarone

Question 1

Amiodarone Drug Class

Answer 1

Class III antiarrhythmic drug

Question 2

Amiodarone MOA

Answer 2

Blocks Na channels at rapid pacing frequencies
Noncompetitive antisympathetic action
Lengthens the cardiac AP
Negative chronotropic effect in nodal tissues
Vasodilatory effects

Question 3

Amiodarone Indications

Answer 3

Recurrent ventricular fibrillation and ventricular tachycardia

Question 4

Amiodarone Contraindications

Answer 4

Cardiogenic shock
Sinus bradycardia
Second or third degree AV block

Question 5

Amiodarone Adverse Effects

Answer 5

Hypotension
Bradycardia and AV block
Liver enzyme elevations
Worsening arrhythmias
Thyroid abnormalities

Question 6

Amiodarone Drug Interactions

Answer 6

Protease inhibitors
Histamine H1 and H2 antagonists
Trazodone
Cyclosporine
HMG-CoA Reductase inhibitors
Digoxin

Question 7

Why does amiodarone cause drug interactions?

Answer 7

Amiodarone is a substrate for CYP3A4 and CYP2C8, drugs interacting with these enzymes will effect serum amiodarone levels or cause QT interval prolongation and torsade de pointes

Question 8

Amiodarone Dosage

Answer 8

150 mg rapid infusion (100 mL D5W)
360 mg over 6 hours (18 mL amiodarone/500 mL D5W) (1 mg/min)
540 mg over 18 hours (0.5 mg/min)