Amiodarone hydrochloride, a class III antiarrhythmic agent used to treat supraventricular and ventricular cardiac dysrhythmias. In this report we describe two patients receiving amiodarone for atrial fibrillation who underwent bone marrow biopsies to investigate paraproteinaemia (case 1) or severe thrombocytopenia (case 2). Multiple bone marrow granulomas were found in both patients, without evidence of any other cause. In both patients the granulomas disappeared after amiodarone withdrawal, suggesting a direct association.