Autonomic dysreflexia is an abnormal, overreaction of the involuntary (autonomic) nervous system to stimulation. This reaction may include:

• Change in heart rate
• Excessive sweating
• High blood pressure
• Muscle spasms
• Skin color changes (paleness, redness, blue-gray skin color)

Autonomic hyperreflexia; Spinal cord injury - autonomic dysreflexia; SCI - autonomic dysreflexia

The most common cause of autonomic dysreflexia (AD) is spinal cord injury. The nervous system of people with AD over-responds to the types of stimulation that do not bother healthy people.

Other causes include:

• Guillain-Barré syndrome (disorder in which the body's immune system mistakenly attacks part of the nervous system)
• Side effects of some medicines
• Severe head trauma and other brain injuries
• Subarachnoid hemorrhage (a form of brain bleeding)
• Use of illegal stimulant drugs such as cocaine and amphetamines

Symptoms can include any of the following:

• Anxiety or worry
• Bladder or bowel problems
• Blurry vision, widened (dilated) pupils
• Lightheadedness, dizziness, or fainting
• Fever
• Goosebumps, flushed (red) skin above the level of the spinal cord injury
• Heavy sweating
• High blood pressure
• Irregular heartbeat, slow or fast pulse
• Muscle spasms, especially in the jaw
• Nasal congestion
• Throbbing headache

Sometimes there are no symptoms, even with a dangerous rise in blood pressure.

AD is life threatening, so it is important to quickly find and treat the problem.

A person with symptoms of AD should:

• Sit up and raise the head
• Remove tight clothing

Proper treatment depends on the cause. If medicines or illegal drugs are causing the symptoms, those drugs must be stopped. Any illness needs to be treated. For example, the provider will check for a blocked urinary catheter and signs of constipation which may cause AD in someone with a spinal cord injury.

If a slowing of the heart rate is causing AD, drugs called anticholinergics (such as atropine) may be used.

Very high blood pressure needs to be treated quickly but carefully, because the blood pressure can drop suddenly.

A pacemaker may be needed for an unstable heart rhythm.

Outlook depends on the cause.

People with AD due to a medicine usually recover when that medicine is stopped. When AD is caused by other factors, recovery depends on how well the disease can be treated.

Complications may occur due to side effects of medicines used to treat the condition. Long-term, severe high blood pressure may cause seizures, bleeding in the eyes, stroke, or death.

Contact your provider right away if you have symptoms of AD.

To prevent AD, do not take medicines that cause this condition or make it worse.

In people with spinal cord injury, the following may also help prevent AD:

• Do not let the bladder become too full
• Pain should be controlled
• Practice proper bowel care to avoid stool impaction
• Practice proper skin care to avoid bedsores and skin infections
• Prevent bladder infections

Published Date: May 02, 2022
Published By: Amit M. Shelat, DO, FACP, FAAN, Attending Neurologist and Assistant Professor of Clinical Neurology, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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