A 16-year-old boy with anorexia nervosa and Ehlers–Danlos syndrome presented with spontaneous pneumomediastinum and bradycardia.Although prior occurrences of pneumomediastinum and visceral perforations have been reported in adolescents with isolated anorexia nervosa or Ehlers–Danlos syndrome, to our knowledge this is the first instance to be noted in a patient with both conditions.We explore several possibilities regarding the etiology of his mediastinal air, but ultimately conclude that it was the existence of Ehlers–Danlos syndrome in the presence of anorexia nervosa that led to the development of this dangerous condition.