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Wernicke Encephalopathy

(Wernicke's Encephalopathy)


Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Grand Strand Medical Center

Reviewed/Revised Dec 2022

Wernicke encephalopathy is caused by a severe deficiency of thiamin Thiamin Deficiency Thiamin deficiency (causing beriberi and other problems) is most common among people whose diet mainly consists of white rice or highly processed carbohydrates in countries with high rates of... read more , a B vitamin. In people who have only a small amount of thiamin stored in the body, it may be triggered by consuming carbohydrates.

Wernicke encephalopathy often develops in people with severe alcohol use disorder Alcohol Use Alcohol (ethanol) is a depressant (it slows down brain and nervous system functioning). Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma,... read more because the long-term use of excess amounts of alcohol interferes with the absorption of thiamin from the digestive tract as well as the storage of thiamin in the liver. Also, people with alcohol use disorder often do not consume an adequate diet and thus not enough thiamin. Wernicke encephalopathy may result from other conditions that cause prolonged undernutrition or vitamin deficiencies. These conditions include dialysis, severe vomiting, starvation, gastric bypass surgery, cancer, and AIDS.

Symptoms of Wernicke Encephalopathy

Diagnosis of Wernicke Encephalopathy

  • A doctor's evaluation

Doctors suspect the diagnosis in people who have the characteristic symptoms and undernutrition or a thiamin deficiency, especially if they are people with alcohol use disorder.

Tests, such as blood tests to measure blood sugar levels, a complete blood cell count, liver tests, and imaging, are usually done to rule out other causes. Thiamin levels are not routinely measured.

Prognosis for Wernicke Encephalopathy

The prognosis depends on how quickly the disorder is diagnosed and treated. Prompt treatment may correct all abnormalities. Eye problems usually improve within 24 hours of treatment. However, loss of balance and confusion may persist days to months, and memory loss may not completely resolve.

Without treatment, about 10 to 20% of people die. 80% of survivors develop Korsakoff psychosis Korsakoff Psychosis Korsakoff psychosis is a complication of long-term thiamin deficiency and causes memory loss for recent events, confusion, and behavioral changes. It is frequently diagnosed along with Wernicke... read more , a disorder in which people develop memory loss, confusion, and behavioral changes. The combination is called Wernicke-Korsakoff syndrome.

Treatment of Wernicke Encephalopathy

  • Thiamin

  • Magnesium

  • Stopping drinking alcohol

Thiamin is given immediately by injection into a vein or muscle. It is continued daily for at least 3 to 5 days. Magnesium, which helps the body process thiamin, is also given by injection or by mouth. Fluids and multivitamins are given, and if levels of electrolytes (such as potassium Hypokalemia (Low Level of Potassium in the Blood) In hypokalemia, the level of potassium in blood is too low. A low potassium level has many causes but usually results from vomiting, diarrhea, adrenal gland disorders, or use of diuretics. A... read more ) are abnormal, they are corrected. Some people may require hospitalization.

People with Wernicke encephalopathy must stop drinking alcohol. Thiamin supplements, taken by mouth, may need to be continued after the initial treatment.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • Alcoholics Anonymous: International fellowship of people with a drinking problem that pioneered the 12-step approach to help its members overcome their addiction to alcohol and help others to do the same.

  • Hazelden Betty Ford Foundation: Nonprofit provider of comprehensive inpatient and outpatient services for adults and young people with addiction and mental health issues.

  • LifeRing: Support for people with drug and alcohol use problems by facilitating sharing of practical experiences and sobriety support as an alternative to traditional 12-step programs.

  • Phoenix House: Helps people combat addiction, regardless of the substance that caused it, through a 12-step program similar to that used by Alcoholics Anonymous.

  • Samaritan Daytop Village: A New York-based agency that helps various populations struggling with addictions, including military veterans, mothers and babies, and homeless people.

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