Introduction Among the symptoms of spinal cord injury are those related to autonomic hyperreflexia which usually follow distension of a hollow viscus or other stimulation below the level of the cord lesion. These symptoms of autonomic hyperreflexia are found for the most part with cervical and high dorsal lesions of the spinal cord. Of most significance are the severe throbbing headache, sweating above the level of the lesion, pilomotor erection, shivering, flushing of the skin, dilated pupils, slow pulse, and significant hypertension, which may be the earliest symptom. When hyperreflexia occurs, the headache begins with a feeling of dullness in the head which then may become throbbing and severe. It may be bitemporal, occipital, or frontal. Blurring of vision may occur. Acute hypertension induced by urinary bladder distention in quadriplegic patients has been well documented by us as well as by others.2-10Our experiment was devised in an attempt