Hypertensive Encephalopathy

Hypertensive encephalopathy is brain dysfunction caused by extremely high blood pressure. It’s reversible with quick treatment but may be life-threatening with severe complications. The first symptoms affect your general wellness, followed by confusion, vision loss and loss of consciousness. Contact emergency services if you have any symptoms.


What is hypertensive encephalopathy?

Hypertensive encephalopathy is a temporary brain dysfunction (change to your mental status) caused by severely high blood pressure. Blood pressure measures the force of blood against your blood vessel walls.

A high blood pressure reading is above 130/80 mmHg. Most adults who experience hypertensive encephalopathy enter the emergency room with a dangerously high reading greater than 220/130 mmHg, but it could sometimes occur with blood pressure readings as low as 160/100 mmHg.

This condition is a medical emergency and can be life-threatening. Common symptoms include headache, restlessness, confusion and seizures. It can lead to coma. Contact 911 or your local emergency services number immediately if you notice symptoms.

How common is hypertensive encephalopathy?

In the United States, high blood pressure emergencies make up less than 2% of all emergency department visits. Hypertensive encephalopathy accounts for 15% of high blood pressure emergencies.


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Symptoms and Causes

What are the symptoms of hypertensive encephalopathy?

The first symptoms of hypertensive encephalopathy you might notice include:

Symptoms that affect your mental status follow and could include:

What causes hypertensive encephalopathy?

Having a severely high blood pressure causes hypertensive encephalopathy.

What are the risk factors for hypertensive encephalopathy?

You may be more at risk of developing hypertensive encephalopathy if you:

  • Don’t know you have high blood pressure.
  • Have recently stopped taking your blood pressure medication(s).
  • Have kidney disease or eclampsia (high blood pressure during pregnancy).
  • Are on certain cancer treatments (chemotherapy).

What are the complications of hypertensive encephalopathy?

Complications of hypertensive encephalopathy may include:

It can be life-threatening.

Diagnosis and Tests

How is hypertensive encephalopathy diagnosed?

To make a hypertensive encephalopathy diagnosis, a healthcare provider will look for changes to your mental status and a high blood pressure reading. This happens during a physical exam and a neurological exam, often in the emergency department. Your healthcare provider will ask you questions about your health history and any medications or supplements you currently take or recently stopped taking.

In addition to a blood pressure reading, your healthcare provider will order tests to assess for organ damage such as:


Management and Treatment

How do you treat hypertensive encephalopathy?

Treatment for hypertensive encephalopathy focuses on lowering your blood pressure using antihypertensive medications. Your healthcare provider will initially give you this medication through a small needle inserted into a vein in your arm rather than through your mouth, to have better management of your blood pressure. Your care team will monitor you closely during treatment in a hospital or intensive care setting. Your provider may start oral medications after eight to 24 hours of reaching your target blood pressure.

If you enter the emergency department with a blood pressure reading of 220/120 mmHg, treatment with antihypertensive medications should lower your blood pressure by 10% to 15% in the first hour. Your blood pressure shouldn’t be lowered more than 25% in 24 hours to allow for healing of your brain’s vessels, as well as not to increase your risk of stroke. Your care team will carefully manage your medication dosage to reduce the risk of side effects.

If you experience seizures, your provider may treat those with antiseizure medications for a short time.

Hypertensive encephalopathy management

Your provider may recommend long-term oral (taken by mouth) antihypertensive medications following your hospital stay for hypertensive encephalopathy. These medications regulate your blood pressure. Your provider may also recommend lifestyle changes, like adjusting what you eat (avoiding sodium or salt) and exercising regularly.

What drugs treat hypertensive encephalopathy?

A healthcare provider will treat hypertensive encephalopathy using fast-acting (rapid-onset) antihypertensive medications, including:

Are there side effects of the treatment?

Side effects from lowering your blood pressure quickly may include:

Many of these side effects are very serious. You’ll be under close observation during your treatment to monitor your progress and prevent complications.

How soon after treatment will I feel better?

You should start to feel better once your blood pressure reduces. This usually happens after 24 to 48 hours. Depending on how encephalopathy affected your brain function, you may need several days to weeks before you feel well again. Complications can affect your recovery time.


Can hypertensive encephalopathy be prevented?

You can’t prevent all cases of hypertensive encephalopathy, but you can significantly reduce your risk by lowering your blood pressure. You can do this by:

  • Eating healthy foods.
  • Lowering your salt intake to less than 2 grams per day.
  • Exercising regularly.
  • Not using tobacco products.
  • Managing your stress.
  • Limiting how much alcohol you drink.
  • Taking antihypertensive medications as directed.

Outlook / Prognosis

What’s the outlook for hypertensive encephalopathy?

Healthcare providers can reverse the effects of hypertensive encephalopathy with careful and quick treatment to reduce your blood pressure. Your encephalopathy symptoms will resolve once your blood pressure lowers. Complications may be more common if you have high blood pressure and another underlying medical condition (comorbidities). Your care team will monitor you during treatment to prevent complications.

After treatment for hypertensive encephalopathy, a healthcare provider will want to check your blood pressure regularly to see how long-term antihypertensive treatment affects you. You can also buy a blood pressure measuring machine, to measure and chart your blood pressure at home, as instructed by your healthcare provider. Let them know if you experience any side effects. Don’t stop taking any blood pressure medications unless your healthcare provider tells you it’s safe to do so.

Living With

When should I see a healthcare provider?

Visit a healthcare provider regularly if you have high blood pressure. They’ll offer treatment and monitor how the treatment affects you. Don’t stop taking blood pressure medications unless your healthcare provider tells you it’s safe. Make your provider aware of any symptoms or side effects you experience.

When should I go to the ER?

Contact 911 or your local emergency services number right away if you have symptoms of hypertensive encephalopathy. Severely high blood pressure is dangerous and can be life-threatening if not treated quickly.

What questions should I ask my healthcare provider?

  • How do I manage my blood pressure?
  • What type of treatment do you recommend?
  • Are there side effects of the treatment?
  • What foods should I avoid to stay healthy?
  • What type of exercise is safe for me to do?

A note from Cleveland Clinic

It isn’t easy to manage your blood pressure. It takes a lot of time and energy to maintain a healthy lifestyle. But complications of severely high blood pressure, like hypertensive encephalopathy, can be life-threatening. While this condition is reversible if treated quickly, you can prevent it by working with your healthcare provider to manage your blood pressure. Never stop taking blood pressure medications unless your provider approves them first.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 11/10/2023.

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