What to know about alcohol and brain damage (excerpt)
By Zawn Villines
Reviewed by Seunggu Han, MD
July 3, 2019
Alcohol begins affecting a person’s brain as soon as it enters the bloodstream. In a healthy person, the liver quickly filters alcohol, helping the body get rid of the drug. However, when a person drinks to excess, the liver cannot filter the alcohol fast enough, and this triggers immediate changes in the brain.
Over time, excessive alcohol consumption can damage both the brain and liver, causing lasting damage.
Excessive alcohol consumption can have long-lasting effects on neurotransmitters in the brain, decreasing their effectiveness or even mimicking them. Alcohol also destroys brain cells and contracts brain tissue. Some people with a history of excessive alcohol use develop nutritional deficiencies that further damage brain function.
The precise symptoms of alcohol-related brain damage depend on a person’s overall health, how much they drink, and how well their liver functions, among other factors.
Short-term effects
Moderate consumption of alcohol may cause a depressed mood, loss of inhibition, and sleepiness.
As soon as alcohol enters the bloodstream, it changes how the brain functions. Moderate consumption of alcohol may cause the following temporary effects:
- loss of inhibition
- decreased planning and organizational skills
- changes in mood and concentration
- difficulty forming new memories
- sleepiness
- depressed mood
- changes in energy levels
- memory loss
- poor judgment
- reduced motor control, including delayed reflexes that can make driving dangerous
People with severe symptoms of intoxication or symptoms that last many hours are at risk of alcohol poisoning.
The ethanol in alcohol acts like a poison. When the liver is not able to filter this poison quickly enough, a person can develop signs of alcohol poisoning or alcohol overdose. An overdose of alcohol affects the brain’s ability to sustain basic life functions.
Symptoms include:
- vomiting
- seizures
- slow heart rate
- difficulty staying awake
- fainting
- low body temperature
- low gag reflex, which can increase the risk of choking if a person vomits
- clammy skin
An untreated alcohol overdose can be fatal. Severe alcohol overdoses may cause permanent brain damage even if the person survives.
The higher a person’s blood alcohol concentration, the higher their risk of alcohol overdose. The heavy consumption of high-alcohol drinks is more likely to cause alcohol poisoning. People who have smaller bodies, drink alcohol less frequently, or have a history of liver disease are also more vulnerable to alcohol poisoning.
Long-term effects
Over time, alcohol abuse can cause permanent brain damage.