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How alcohol affects the brain

Alcohol interferes with communication pathways in the brain. This causes the loss of control that happens when you are drunk.

In the longer term, drinking too much alcohol can damage, shrink or kill brain cells. This can change the way the brain works.

Alcohol can affect the brain in different ways to cause problems.

Some of these problems include:

  • lowering the level of serotonin in the brain, which can lead to depression
  • stopping new brain cells developing
  • damaging nerve cells and blood vessels in the brain

Alcohol-related brain injury

Drinking heavily over a long period of time can cause long-lasting or permanent changes to the brain.

The symptoms of alcohol-related brain injury include:

  • poor memory
  • difficulties with new learning
  • balance and coordination problems
  • changes in temperament or personality
  • attention and concentration difficulties
  • mental health problems, like anxiety and depression

Wernickes-Korsakoff’s Syndrome (wet brain)

Wernickes-Korsakoff’s Syndrome is a brain disorder. It is also known as 'wet brain'.

It is caused by a lack of vitamin B1 (thiamine).

Many dependent drinkers lack vitamin B1. This can be from a bad diet and because alcohol affects how your body absorbs and uses vitamin B1.

Wernickes-Korsakoff’s Syndrome includes 2 separate but related conditions:

  • Wernicke Encephalopathy
  • Korsakoff’s Amnesic Syndrome


This is a short-lived but life-threatening condition.

Symptoms include:

  • muscle problems (ataxia) - legs may tremble or you may walk with your legs spread wide apart
  • not being able to move your eyes normally, jerking movements in the eyes or double vision
  • being confused and not understanding what’s happening

Non-urgent advice: Speak to your GP if:

  • you notice any symptoms of Wernicke encephalopathy

If not treated, you can die from Wernicke's-Encephalopathy. It can also lead to the development of Korsakoff's-Amnesic Syndrome.

Korsakoff’s-Amnesic Syndrome

This is a longer-lasting brain disorder.

Symptoms include:

  • not being able to remember things, create new memories, or learn new information
  • filling up gaps in the memory with made-up stories

Alcohol and the teenage brain

From the age of 12 your brain starts to undergo some radical changes. These continue until you are in your mid-20s.

During this time, the brain is developing more sophisticated abilities and skills.

These changes allow you to act in a more sophisticated way.

They give you the ability to:

  • problem solve
  • make sense of complex information
  • make plans for your future

Teenagers should not drink alcohol during this time. This is because the brain is under construction and being ‘recoded’. Drinking can disrupt this process.

Alcohol use affects many functions of the brain, including:

  • learning
  • remembering
  • problem-solving

The teenage brain is also more likely to become addicted to alcohol than the adult brain. Teenagers who drink before the age of 15 are more likely to misuse alcohol in later life.

Alcohol and the older brain

As we get older, the body’s ability to process and clear alcohol from your body changes. For example, there is a reduction in your muscle mass as you get older. There is also less water stored in the body. This means that alcohol becomes more concentrated in our system.

As we age, we are also more likely to:

  • experience physical health problems
  • take medicine
  • be at greater risk for other disorders of the brain, for example, dementia

Because of this, older people tolerate alcohol less well than younger people. They are more sensitive to the negative effects of alcohol. This means they experience more harm from alcohol use than other adults.

Physical problems can happen at lower levels of drinking in older people.

It can lead to a higher risk or likelihood of making some health problems worse.

These include:

  • coronary heart disease
  • hypertension
  • stroke
  • insomnia
  • gastrointestinal problems
  • self-neglect, including poor nutrition, poor hygiene and hypothermia
  • increased chance of cancer of the liver, oesophagus, nasopharynx and colon
  • cirrhosis of the liver

You have a higher risk of falling as a result of drinking as you get older. You are also more likely to seriously injure yourselves if you do fall.

Page last reviewed: 19 September 2022
Next review due: 19 September 2025