Blacking out doesn’t necessarily mean you are an alcoholic. But it is a sign of unsafe drinking habits that can be part of or lead to alcoholism.
Drinking to a dangerous level can cause a blackout, or a period when your brain is unable to form new memories, even though you are awake and making decisions. Unlike passing out, blacking out does not stop you from reacting to events around you, which can be extremely dangerous.
Binge drinking can lead to a blackout. While binge drinking is not a symptom of alcoholism, or alcohol use disorder, people who are addicted to alcohol are more likely to binge drink more often, which increases their risk of blacking out.
What Is a Blackout From Drinking?
Drinking too much can lead to a blackout, or the temporary inability to form memories of what is going on around you. This is not the same thing as passing out, when you become unconscious because of the amount of alcohol you drank; however, blacking out is still very dangerous.
Although you do not remember what happened, you are fully awake, reacting to what happens around you and making decisions. The reduced inhibitions and poor decision-making associated with being drunk can cause you to do dangerous things, but you will not remember what happened.
The brain’s response that leads to blacking out is just being understood, but researchers believe that alcohol interferes with receptors in the brain that produce steroids that inhibit long-term potentiation (LTP). When functioning normally, this process strengthens the connections between neurons in the hippocampus, which aids learning and memory. The presence of large amounts of alcohol cuts the presence of LTP in half, which means the brain does not move short-term memory into long-term memory until alcohol metabolizes out of the brain.
Sometimes, you can remember what happened if a friend reminds you of events the night before, but this does not always happen. Some people are more prone to experiencing blackouts than others, but blacking out does indicate binge drinking or high-risk drinking. This is very dangerous for your health, whether you black out, pass out, or stay fully conscious.
Dangers of Blacking Out
A blackout may indicate a fully lost memory or a vague, hazy memory of what happened between clearer memories. Blood alcohol concentration (BAC) typically needs to be dangerously high for a blackout to occur. People who drink a lot of alcohol very quickly tend to experience more gaps in their memory than others, suggesting that they experience more blackouts. However, blackouts occur on average when BAC reaches 0.16 percent, which is more than twice the legal limit to drive in most of the US.
There are several risk factors that increase the chance of blacking out, like:
- Being female because women tend to have lower body water to dilute alcohol.
- Smoking, which often indicates abuse of other substances.
- Having friends who also drink a lot and abuse other drugs.
- Combining drugs, like prescription painkillers or anti-anxiety medication.
- Presenting impulsive and sensation-seeking behaviors.
The main factor is drinking well past your body’s tolerance, or binge drinking. Binge drinking is typically defined as four or more servings of alcohol for women, or five or more servings of alcohol for men, over two hours or less.
Lots of people binge drink and do not realize that this is dangerous behavior. Binge drinking is so common, and it is not considered a type of alcohol use disorder, or alcoholism. However, many people who struggle with alcohol addiction do binge drink.
A survey of English teenagers who drank found that 30 percent of 15-year-old teens and 75 percent of 19-year-old teens experienced alcohol-related blackouts because of the amount they drank. A similar survey found that 90 percent of 19-year-old teens in England had experienced at least one blackout, and about half had experienced multiple blackouts. More than half reported having at least one blackout every year at their follow-up.
One in six adults in the United States binge drinks four times per month, consuming seven drinks on average per binge. This problem is most common among people ages 18 to 34, but older adults also frequently binge drink. Binge drinking is also more common among people who have higher incomes and more education.
More than 90 percent of adults in the US who report excessive drinking note at least one binge episode in the past month.
Consequences of Blackouts
Experiencing a blackout from alcohol does not mean that you are an alcoholic, but it does mean you have engaged in dangerous drinking behavior that puts your BAC past your body’s tolerance.
If you black out once, you might realize that this is a problem and avoid binge drinking in the future; however, if you have frequent blackouts, especially if you think blackouts are normal when drinking, you likely have other issues related to alcohol abuse.
Research suggests that more frequent blackouts are linked to other consequences like these:
- Missing work or school
- Having a lower school GPA
- Suffering injury from an accident
- Being hospitalized
- Being arrested for drunk driving
- Losing money or harming relationships
Since blackouts are associated with binge drinking, you are more likely to have impaired motor coordination, lowered inhibitions, and poor impulse control. You are more at risk of engaging in drunk driving, unprotected sex, or other dangerous behaviors.
Long term, binge drinking has been linked to a reduced ability to learn new things, especially verbally. Binge drinking is also associated with altered brain development in adolescents.
Too often, people who binge drink as a form of socializing black out but shake it off, believing it to be normal for everyone or a good story for later. In fact, frequent binge drinking that results in blacking out is dangerous for both your short-term and long-term health, and it can indicate that you have a dependence or addiction to alcohol.
Getting Help for Alcohol Use Disorder
When you seek treatment for alcohol use disorder, start with a physician or therapist who can diagnose the severity of your addiction. Compulsive behaviors can involve drinking very little but still benefit from behavioral therapy in rehab, while drinking high volumes for a long time may require intervention with prescription medications to detox safely.
Evidence-based treatment with several approaches to detox and rehabilitation are becoming more common. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) has a list of treatment providers you can search on their website, along with recommendations for questions to ask so you can find a treatment provider who suits your needs.
Experiencing one blackout from drinking too much means you did something dangerous, but it does not mean you have a problem with alcohol. However, if you experience blackouts regularly, you are drinking too much and too often. Treatment can help you overcome compulsive behaviors and focus on your health.
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