Autonomic dysreflexia is a syndrome characterized by abrupt onset of excessively high blood pressure caused by uncontrolled sympathetic nervous system discharge in persons with spinal cord injury. Persons at risk for this problem generally have injury levels above T-6. True autonomic dysreflexia is potentially life-threatening and is considered a medical emergency.

What are signs and symptoms of Autonomic Dysreflexia?

  • Hypertension (blood pressure greater than 200/100)
  • Pounding headache (secondary to hypertension)
  • Flushed (reddened) face
  • Red blotches on the skin above level of spinal injury
  • Sweating above level of spinal injury
  • Nasal stuffiness
  • Nausea
  • Bradycardia – slow pulse <60 beats per minute –
  • Piloerection (“goose bumps”) below level of spinal injury
  • Cold, clammy skin below level of spinal injury


There can be many stimuli that cause autonomic dysreflexia.

Anything that would have been painful, uncomfortable, or physically irritating before the injury may cause autonomic dysreflexia after the injury.

The most common cause seems to be overfilling of the bladder. This could be due to a blockage in the catheter, bladder infection (cystitis), inadequate bladder emptying, bladder spasms, or possibly stones in the bladder. The second most common cause is a bowel that is full of stool or gas. Any stimulus to the rectum, such as digital stimulation, can trigger a reaction, leading to autonomic dysreflexia.

Other causes include skin irritations, wounds, pressure sores, burns, broken bones, pregnancy, ingrown toenails, appendicitis, and other medical complications