When to Hold Amiodarone

Cardiovascular Reasons to Hold Amiodarone

The American Academy of Family Physicians recommends holding amiodarone in patients with second- or third-degree heart block who do not have a pacemaker, as it is contraindicated in these populations 1, 2
Discontinue or reduce infusion rate if bradycardia (occurs in 1-3% of oral therapy patients and 4.9% of IV therapy patients) or heart block develops during treatment 2, 3
Stop infusion or reduce the rate if hypotension occurs (seen in 16% of patients receiving IV amiodarone) 2, 3
Consider holding in patients with significant QT prolongation, as amiodarone can further prolong the QT interval (although torsades de pointes is rare with amiodarone) 1, 3

Immediately hold amiodarone if there are signs of pulmonary toxicity, which is the most serious non-cardiac adverse effect (occurs in 2-17% of patients) 4, 5
Any report of worsening dyspnea or cough should prompt immediate assessment and consideration of holding amiodarone 4, 5
Pulmonary toxicity typically presents as subacute cough and progressive dyspnea with interstitial infiltrates on chest radiographs 4, 5

Hold amiodarone if liver enzyme levels are three times higher than normal, unless the patient is at high risk for recurrence of life-threatening arrhythmia 4, 5

Consider holding amiodarone if thyroid dysfunction (occurs in 2-10% of patients) becomes severe and cannot be managed with appropriate therapy 4
Refer patients with changes in visual acuity or peripheral vision for ophthalmologic evaluation and consider holding the medication if optic neuropathy is confirmed 4

When initiating amiodarone in patients on warfarin, reduce warfarin dose by one-third to one-half and monitor INR closely (at least weekly for first 6 weeks) 1
For patients on digoxin, reduce digoxin dose by approximately 50% when starting amiodarone, as digoxin levels typically double 1

Monitor liver function tests and thyroid studies every 6 months during maintenance therapy 1, 2
Perform chest radiograph and pulmonary function tests if pulmonary toxicity is suspected 1, 2
Closely monitor heart rate, especially during the first week of treatment 1, 2
For patients on warfarin, check prothrombin time and INR at least once weekly during the first 6 weeks of treatment 1, 2

Hold or reduce the rate of IV amiodarone if heart block, bradycardia (4.9% of patients), or hypotension (16% of patients) occurs 2
IV amiodarone should not be used in patients with bradycardia or heart block who do not have a pacemaker 2

The American Heart Association recommends continuing close INR monitoring and adjusting warfarin dose upward gradually as amiodarone clears, due to the persistent interaction during elimination 6
The American College of Cardiology suggests considering whether the patient needs alternative rhythm control strategies before discontinuing amiodarone, as the first sign of antiarrhythmic failure may be sudden cardiac death 7