Prostaglandin administration is the main therapy for ductal-dependent congenital heart disease prior to definitive therapy. We report a case in which tetralogy of Fallot and Noonan syndrome were diagnosed, complicated by small pulmonary arteries, which occasioned a delay in surgery. Treatment was started with prostaglandins, which were given for a total of 2 months, and a diffuse periosteal reaction occurred secondary to the administration of intravenous prostaglandin E1.