Amiodarone-induced pulmonary toxicity. Predisposing factors, clinical symptoms and treatment.

Amiodarone is frequently used for the treatment of cardiac arrhythmias. Although the therapeutic efficacy of amiodarone has been established, its use is limited by its safety profile. Amiodarone-induced pulmonary toxicity is one of the most life-threatening complications of this therapy. It is a relatively rare adverse effect of amiodarone and is easily missed by any physician who is suddenly confronted with nonspecific pulmonary complaints during amiodarone treatment. There are several cumulative factors which may enhance the susceptibility of patients for amiodarone-induced pulmonary toxicity, such as advanced age and pre-existing pulmonary dysfunction. Several case studies and clinical trials of amiodarone have shown the possible occurrence of amiodarone-induced pulmonary toxicity during low dose and short-duration therapy. Therefore, the dose and duration of amiodarone treatment are not the only determinants of toxicity risk. Amiodarone-induced pulmonary toxicity is characterised by various clinical manifestations such as coughing, dyspnoea, fever, bodyweight loss, respiration-related chest pain and bilateral lung infiltrates with no excavated nodules. Once amiodarone-induced pulmonary toxicity has been diagnosed, therapeutic options are limited, but in most cases the disease is reversible, if diagnosed at an early stage.