Autonomic Dysreflexia

Medically Reviewed by James Beckerman, MD, FACC on September 02, 2022

Autonomic dysreflexia is a serious medical problem that can happen if you’ve injured your spinal cord in your upper back. It makes your blood pressure dangerously high and, coupled with very low heartbeats, can lead to a stroke, seizure, or cardiac arrest.

This happens when your autonomic nervous system -- which controls things like breathing and digestion that you do without thinking -- overreacts to something below the damaged spinal cord. It’s sometimes called hyperreflexia. More than half of people with a spinal cord injury in the upper back get it.

Autonomic dysreflexia is an emergency and needs immediate medical attention. It can be life-threatening.

You can get autonomic dysreflexia if you’ve injured your spinal cord around the bottom of the shoulder blades or above. You can lose feeling and muscle control below the damaged spot. But the nerves there still try to send signals back to the brain. That can make your body do the wrong thing.

For example, your blood vessels may react to the faulty signals and become narrower, which makes your blood pressure go up. Your brain tries to lower your blood pressure, but its message can’t get past the damaged part of the spinal cord. High blood pressure can give you a heart attack or a stroke.

The first signs of autonomic dysreflexia usually are a flushed feeling or a pounding headache. You also may have:

Something as simple as a full bladder or an ingrown toenail can be enough to send your nerve responses into overdrive. Other things that can set off the condition include:

Your doctor will measure your blood pressure while they figure out what triggered your autonomic dysreflexia episode. They’ll check your bladder and bowels, since fullness or a blockage there is usually the cause of the problem.

You may need imaging tests, like X-rays or an ultrasound, or lab tests on your blood or urine.

If you have autonomic dysreflexia symptoms, here are a few things you can do until you can get medical help:

  • Sit up as much you can. This helps move more blood to your lower body and ease your blood pressure
  • Take off tight clothes or other irritants
  • Pee

Quick steps can keep the problem from getting worse. Your doctor may give you medication to make your blood pressure drop quickly. If the problem is severe, they may watch your blood pressure for 2-48 hours.

You can take steps to lower your chance of complications:

  • Use the bathroom on a regular schedule. Keep your bladder and bowels from becoming too full.
  • Know the signs of a bladder infection.
  • Take care not to get skin sores or ingrown toenails.
  • Carry a card for emergencies to let people know you might have autonomic dysreflexia.

Autonomic dysreflexia can be a life-threatening condition. It can cause bleeding in the brain, stroke, seizures, and other heart and lung problems.

Show Sources


Archives of Physical Medicine and Rehabilitation: “A systematic review of the management of autonomic dysreflexia following spinal cord injury.”

The Journal of Spinal Cord Medicine: “Life-threatening outcomes associated with autonomic dysreflexia: A clinical review.”

National Institute of Neurological Disorders and Stroke: “Spinal Cord Injury: Hope Through Research.”

The Shepherd Center: “Autonomic dysreflexia.”

The Reeve Foundation: “Autonomic dysreflexia.”

Postgraduate Medical Journal: "Autonomic dysreflexia: a medical emergency."

Canadian Family Physician: “Autonomic dysreflexia -- Recognizing a common serious condition in patients with spinal cord injury.”

American Academy of Physical Medicine and Rehabilitation: “Autonomic Dysreflexia in Spinal Cord Injury.”

StatPearls: “Autonomic Dysreflexia.”

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