Abstract
A 63-year-old man was prescribed bepridil for paroxysmal atrial fibrillation in May 2011. He was referred to our hospital with the chief complaint of slight dyspnea in October 2012. Radiography and computed tomography indicated diffuse bilateral peribronchial infiltration. Since an examination of the bronchial alveolar lavage fluid revealed inflammatory lymphocytes and a drug lymphocyte stimulation test was strongly positive for bepridil, he was diagnosed with bepridil-induced interstitial pneumonia. In our case, the patient developed dyspnea 517 days after beginning bepridil treatment. Here, we describe an extremely rare case of late onset interstitial pneumonia induced by bepridil.