Management of Amiodarone-Induced Interstitial Lung Disease (ILD)

Clinical Presentation and Diagnosis

Amiodarone-induced pulmonary toxicity most commonly presents as subacute cough and progressive dyspnea, with associated patchy interstitial infiltrates on chest radiographs and reduced diffusing capacity on pulmonary function tests 1
Less commonly, it may present as acute respiratory distress syndrome (ARDS), which occurs at a rate of approximately 1% annually in patients taking amiodarone 1
Diagnosis is one of exclusion, requiring ruling out other causes such as congestive heart failure, which can mimic amiodarone pneumonitis 1

The primary treatment for amiodarone-induced pulmonary toxicity is immediate withdrawal of amiodarone and provision of supportive care, with corticosteroids often indicated in more severe cases 1, 2
Discontinue amiodarone as the first and most critical intervention 1
Provide supportive care to maintain adequate oxygenation 1
Initiate corticosteroid therapy (typically prednisone) in moderate to severe cases 1
Any report of worsening dyspnea or cough should prompt immediate assessment for pulmonary toxicity 1
Delaying discontinuation of amiodarone once pulmonary toxicity is suspected is a common pitfall to avoid 1
Continuing amiodarone in patients with confirmed pulmonary toxicity unless the patient is at high risk for recurrence of life-threatening arrhythmia with no alternative treatment options 1

Use the lowest possible effective dosage of amiodarone to reduce risk 1
Any report of worsening dyspnea or cough should prompt immediate assessment for pulmonary toxicity 1

Amiodarone pneumonitis most commonly presents as subacute cough and progressive dyspnea with patchy interstitial infiltrates on chest radiographs, reduced diffusing capacity on pulmonary function tests, and ground-glass opacities on high-resolution CT scanning 3
Less commonly, it may present as acute respiratory distress syndrome, occurring in approximately 1% of cases annually 3
High-resolution CT scanning is helpful in making the diagnosis, particularly in excluding other conditions such as congestive heart failure and lung infection 3

Due to amiodarone's accumulation in fatty tissues and long elimination half-life, averaging 58 days, pulmonary toxicity may initially progress despite drug discontinuation and may recur after steroid withdrawal 4
Routine screening has limited value because pulmonary toxicity can develop rapidly with no antecedent abnormalities on chest radiographs or pulmonary function tests 3

In most instances, the toxicity is reversible with immediate withdrawal and prompt steroid therapy 3
The prognosis of amiodarone lung disease is generally favorable with appropriate management, with full recovery expected in most cases 3