The features of headache attributed to autonomic dysreflexia after spinal cord injury (SCI) were determined by a literature search at the University of Toronto, Canada. Presenting features were sudden onset, severe throbbing headache, accompanied by increased blood pressure, altered heart rate, cutaneous vasodilation, hyperhidrosis and flushing cranial to the level of SCI, blurred vision, syncope, and anxiety. Triggers of the headache include bladder distension, constipation, sunburn, menstruation, and pulmonary infarct. 
COMMENT. Autonomic dysreflexia after SCI (at T6 or above) is characterized by initial low blood pressure and bradycardia, followed by volatile and episodic extreme hypertension, accompanied by headache and upper body flushing provoked by triggers. A triad of cephalalgia, hyperhidrosis, and cutaneous vasodilation occurs in 85% cases. The prevalence of SCI in children is 2.4/million and 25/million in adolescents, mainly car and motorcycle accidents. (Hagen EM et al. Spinal cord 201 l;May 10. Epub ahead of print).