Wernicke encephalopathy and Korsakoff syndrome are different conditions that often occur together. Both are due to brain damage caused by a lack of vitamin B1.

Lack of vitamin B1 is common in people who have alcohol use disorder. It is also common in people whose bodies do not absorb food properly (malabsorption). This can sometimes occur with a chronic illness or after weight-loss (bariatric) surgery.

Korsakoff syndrome, or Korsakoff psychosis, tends to develop as Wernicke encephalopathy as symptoms go away. Wernicke encephalopathy causes brain damage in lower parts of the brain called the thalamus and hypothalamus. Korsakoff psychosis results from permanent damage to areas of the brain involved with memory.

Symptoms of Wernicke encephalopathy include:

• Confusion and loss of mental activity that can progress to coma and death
• Loss of muscle coordination (ataxia) that can cause leg tremor
• Vision changes such as abnormal eye movements (back and forth movements called nystagmus), double vision, eyelid drooping
• Alcohol withdrawal

Symptoms of Korsakoff syndrome include:

• Inability to form new memories
• Loss of memory, can be severe
• Making up stories (confabulation)
• Seeing or hearing things that are not really there (hallucinations)

Examination of the nervous/muscular system may show damage to many nerve systems:

• Abnormal eye movement
• Decreased or abnormal reflexes
• Fast pulse (heart rate)
• Low blood pressure
• Low body temperature
• Muscle weakness and atrophy (loss of muscle mass)
• Problems with walk (gait) and coordination

The person may appear poorly nourished. The following tests are used to check a person's nutrition level:

• Serum albumin (relates to person's general nutrition)
• Serum vitamin B1 levels
• Transketolase activity in red blood cells (reduced in people with thiamine deficiency)

Liver enzymes may be high in people with a history of long-term alcohol abuse.

Other conditions that may cause vitamin B1 deficiency include:

• HIV/AIDS
• Chemotherapy or cancers that have spread throughout the body
• Extreme nausea and vomiting during pregnancy (hyperemesis gravidarum)
• Heart failure (when treated with long-term diuretic therapy)
• Long periods of intravenous (IV) nutrition without receiving thiamine supplements
• Long-term dialysis
• Very high thyroid hormone levels (thyrotoxicosis)

A brain MRI may show changes in the tissue of the brain. But if Wernicke-Korsakoff syndrome is suspected, treatment should start immediately. Usually a brain MRI exam is not needed.

The goals of treatment are to control symptoms and to prevent the disorder from getting worse. Some people may need to stay in the hospital early in the condition to help control symptoms.

Monitoring and special care may be needed if the person is:

• In a coma
• Lethargic
• Unconscious

Vitamin B1 is usually given by injection into a vein or a muscle as soon as possible. This may improve symptoms of:

• Confusion or delirium
• Difficulties with vision and eye movement
• Lack of muscle coordination

Vitamin B1 often does not improve loss of memory and intellect that occur with Korsakoff syndrome.

Stopping alcohol use can prevent more loss of brain function and damage to nerves. A well-balanced, nourishing diet can help, but it is not a substitute for stopping alcohol use.

Without treatment, Wernicke-Korsakoff syndrome gets steadily worse, and can be life threatening. With treatment, it is possible to control symptoms (such as uncoordinated movement and vision difficulties). This disorder can also be slowed or stopped.

Complications that may result include:

• Alcohol withdrawal
• Difficulty with personal or social interaction
• Injury caused by falls
• Permanent alcoholic neuropathy
• Permanent loss of thinking skills
• Permanent loss of memory
• Shortened life span

Contact your health care provider or go to the emergency room if you have symptoms of Wernicke-Korsakoff syndrome, or if you have been diagnosed with the condition and your symptoms get worse or return.

Not drinking alcohol or drinking in moderation and getting enough nutrition reduce the risk of developing Wernicke-Korsakoff syndrome. If a heavy drinker will not quit, thiamine supplements and a good diet may reduce the chance of getting this condition, but the risk is not eliminated.

Korsakoff psychosis; Alcoholic encephalopathy; Encephalopathy - alcoholic; Wernicke's disease; Alcohol use - Wernicke; Alcoholism - Wernicke; Thiamine deficiency - Wernicke

Koppel BS, Weimer LH, Daras M. Nutritional and alcohol-related neurologic disorders. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 384.

So YT. Deficiency diseases of the nervous system. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 85.

Updated by: Joseph V. Campellone, MD, Department of Neurology, Cooper Medical School at Rowan University, Camden, NJ. 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.