Amiodarone-Induced Interstitial Pneumonia: A Cause of Respiratory Failure

Amiodarone, a widely used antiarrhythmic medication, is effective for managing various types of cardiac arrhythmias. However, due to its high lipid solubility and long half-life, amiodarone accumulates in various organs, particularly the lungs. Pulmonary toxicity, while rare (1% to 5% incidence), is among the most serious adverse effects of amiodarone, with interstitial pneumonitis (IP) being the most prevalent form of lung toxicity. Recognized risk factors are old age, high daily doses, and long-lasting therapy. Amiodarone-induced interstitial pneumonia (AIP) is a rare but serious complication of amiodarone therapy, often presenting as progressive respiratory failure. Patients with AIP typically present with nonspecific respiratory symptoms, including dyspnea, cough, and occasionally fever, making the initial diagnosis challenging. Diagnosing AIP requires a combination of clinical, radiological, and histological data, with computed tomography (CT) often revealing ground-glass opacities and interstitial thickening. Management of AIP focuses on discontinuing amiodarone and initiating corticosteroid therapy. Early withdrawal of amiodarone is crucial for symptom resolution and preventing progression to severe lung injury or irreversible fibrosis. We report an 89-year-old female patient with chronic use of amiodarone who was medicated with high doses of the drug during hospitalization and started presenting signs of respiratory failure. The radiological findings were consistent with AIP, and the patient improved with drug discontinuation and a trial of glucocorticoid therapy. AIP is a critical but preventable cause of respiratory failure in patients undergoing antiarrhythmic therapy. Awareness among healthcare providers about this complication, along with timely diagnosis and management, is essential to improving patient outcomes.