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Autonomic Dysreflexia of the Spinal Cord


Michael Rubin

, MDCM, New York Presbyterian Hospital-Cornell Medical Center

Reviewed/Revised Feb 2023

Autonomic dysreflexia of the spinal cord is an overreaction of the autonomic nervous system that occurs in people with a spinal cord injury, causing life-threatening high blood pressure (hypertension).

Autonomic dysreflexia occurs 1 month to 1 year later in 20% to 70% of people who have had a spinal cord injury.

The autonomic nervous system is the part of the nervous system that regulates body processes, such as blood pressure, urination, bowel movements, digestion, erection, breathing, vision, sweating, and salivation. When the spinal cord is injured, certain nerves in the autonomic nervous system may overreact to the injury or to some other problem, causing blood vessels to narrow and blood pressure to increase. Normally, other autonomic nerves send signals down the spinal cord to widen blood vessels, allowing the blood vessels to carry more blood and thus lower blood pressure. However, when the spinal cord is injured, nerve signals cannot always travel down the spinal cord to widen blood vessels, and blood pressure may remain high.

Autonomic dysreflexia may be triggered by

Symptoms of Autonomic Dysreflexia

Symptoms of autonomic dysreflexia vary. They usually begin suddenly and occur intermittently.

People with this disorder may have headaches. They may feel nauseated and vomit. They may sweat profusely and be flushed. The skin may be dry and pale. Other symptoms include problems with vision, nasal congestion, and feelings of anxiety and doom.

High blood pressure may suddenly increase even more (called hypertensive emergency Classification of blood pressure Classification of blood pressure ). Hypertensive emergency is life-threatening. People with hypertensive emergency may have a severe, throbbing headache, blurred vision, confusion, chest pain, shortness of breath, and seizures.

Diagnosis of Autonomic Dysreflexia

  • A doctor's evaluation

Doctors suspect autonomic dysreflexia when people have a spinal cord injury in the upper back and very high blood pressure, especially if they also have a distended bladder or intestine.

They also check for possible triggers of autonomic dysreflexia, such as a distended bladder.

Treatment of Autonomic Dysreflexia

  • Correction of the cause

  • Control of blood pressure

Doctors remove or correct the problem causing autonomic dysreflexia.

Very high blood pressure is immediately treated with medications that work quickly, such as nitroglycerin, hydralazine, labetalol, or nifedipine.

Doctors may refer pregnant women to an obstetrician who specializes in treating disorders such as autonomic dysreflexia.

OnabotulinumtoxinA (a medication used to block nerve activity), injected into the main bladder muscle, may help prevent episodes of autonomic dysreflexia.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Deponit, GONITRO , Minitran, Nitrek, Nitro Bid, Nitrodisc, Nitro-Dur, Nitrogard , Nitrol, Nitrolingual, NitroMist , Nitronal, Nitroquick, Nitrostat, Nitrotab, Nitro-Time, RECTIV, Transdermal-NTG, Tridil
No brand name available
Normodyne, Trandate
Adalat, Adalat CC, Afeditab CR, Nifediac CC, Nifedical XL, Procardia, Procardia XL
Botox, Botox Cosmetic
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