Alcohol Blackouts

Alcohol is among the most popular recreational drugs in the United States, despite the fact that it is powerfully addictive. Alcohol abuse has serious social, health and legal ramifications. According to the National Institute on Alcohol Abuse and Alcoholism, 15.1 million American adults and 623,000 adolescents meet the criteria for having an alcohol use disorder. More than 13% of teenagers report that they binge drink. Among the dangers of alcohol use is the risk of a blackout.

Understanding Alcohol-Induced Blackouts

Alcohol-induced memory loss, often referred to as a “blackout,” is a common side effect of excessive alcohol consumption (i.e., binge drinking). Blackouts are a breakdown in the transfer of information from short-term to long-term storage. Blackouts can be a complete or fragmentary loss of memory of the hours surrounding drinking.

Alcohol, directly and indirectly, inhibits activity in a structure in the brain called the hippocampus, which is responsible for forming memories. The hippocampus is particularly sensitive to alcohol, and binge drinking temporarily prevents memory formation in the hippocampus, a mental state that is known as temporary anterograde amnesia. Alcohol-induced memory impairments are dose-dependent.

Although they may not be obvious at lower doses, laboratory-controlled studies have shown that even moderate amounts of alcohol interfere with memory formation.

What Causes Alcohol Blackouts?

The most obvious factor that contributes to alcohol-related amnesia is the amount of alcohol consumed. If you drink more than your body can metabolize, you put yourself at risk of experiencing a blackout. The liver can metabolize approximately one drink per hour. Unmetabolized alcohol remains in the bloodstream, which is why blood alcohol content (BAC) rises as you continue to consume alcohol.

While it is known that some people are more prone to alcohol-induced amnesia than others are, the reason for this difference is unclear. Intrinsic factors like genetics, weight and nourishment play a role, as do extrinsic factors like alcohol tolerance, the presence of other drugs and exercise frequency.

  • Genetics: Just as alcohol addiction is often tied to genetics, blacking out may be tied to genetics as well. Recent studies have indicated that alcohol blackouts tend to run in families.
  • Weight: Your body weight will affect your risk for blacking out. The less you weigh, the easier it will be for you to consume too much alcohol.
  • Nourishment: You are more vulnerable to a blackout if you are drinking while you are malnourished. Often, people who struggle with alcoholism don’t get the proper nutrition they need. Even if you don’t drink on an empty stomach, drinking alcohol regularly may interfere with your ability to absorb nutrients from the food you have consumed.

Types of Blackouts

Generally speaking, there are two types of alcohol-induced blackouts:

  • Fragmentary blackouts: Fragmentary blackouts indicate that alcohol-related memory loss is partial. The terms “brown-out,” or “grey-out” have been used to distinguish fragmentary blackouts from en bloc blackouts. Fragmentary blackouts often include memories that can be recalled with an appropriate cue.
  • En bloc blackouts: An en bloc blackout indicates that complete memory loss for the hours surrounding excessive alcohol use has occurred. En bloc blackouts are usually associated with higher blood alcohol content.

Fragmentary blackouts can occur with a breath alcohol concentration (BrAC) as low as 0.06 g/dL but most evidence indicates that blackouts are associated with a BrAC of at least 0.14 g/dL and more commonly at a level of 0.20 g/dL or greater.

It is important to distinguish between alcohol-induced blackouts and unconsciousness: Blackouts occur when people are conscious and can interact with and respond to their environment in some capacity. Unconsciousness refers to a state where someone is unable to interact with or respond to their environment.

Symptoms and Signs of Alcohol Blackouts

A symptom is a subjective, qualitative measure of a condition that affects someone. Asking someone to describe symptoms of an alcohol blackout is like asking someone to remember not remembering.

Signs, on the other hand, are objectively measurable by observers. Signs of alcohol blackouts include impairments in motor control (the loss of balance, slurred speech) or the loss of impulse control (poor decision making, erratic behavior).

Side Effects of Alcohol Blackouts

Alcohol-induced blackouts can cause short- and long-term side effects. Knowing the side effects can help people recognize if they are, or have, experienced alcohol amnesia.

The short-term side effects of alcohol-induced amnesia are unlikely to be remembered by someone who has blacked out due to excessive alcohol consumption. Young women are at particular risk for unintended short-term ramifications, including sexual assault.

It is not uncommon for people to wake up at home, in someone else’s home or even in jail without remembering how they got there. Data from the U.S. Department of Justice indicates that nearly 40% of arrestees were drinking alcohol when they committed their crime.

Alcohol-induced blackouts are characterized by irrational behavior, even among people who are normally thoughtful and level-headed. As a result, long-term side effects may include sexually transmitted infections, unintended pregnancy, erratic or violent behavior or arrest.

Regular, heavy alcohol use can cause significant damage to the brain and other organs. Liver damage is notoriously associated with heavy alcohol use, but irreversible brain damage is another consequence of heavy alcohol use, especially if someone drinks heavily during adolescence.

Dangers of Alcohol Amnesia

Alcohol-induced amnesia is associated with extremely dangerous short- and long-term consequences. Duke University researchers recently conducted a survey of the activities of 772 people who experienced alcohol-induced blackouts. They found that of these 772 people:

  • 27% spent money
  • 24% engaged in sexual activity
  • 16% got into a fight
  • 16% vandalized property
  • 6% had unprotected sexual intercourse
  • 3% drove a car

The excuse of not remembering a crime due to a blackout from drinking alcohol doesn’t tend to sit well with a judge, and often, people who suffer from alcohol addiction will serve time in prison for a crime they can’t remember committing.

Tips to Avoid Alcohol Blackouts

  • Stay hydrated: Dehydration from alcohol consumption is a consequence of alcohol’s ability to increase urinary output. Staying hydrated while drinking alcohol is important for controlling inebriation and it can also limit the severity of the next-day hangover.
  • Eat a meal: Alcohol is absorbed in the small intestine, so eating food when you are drinking alcohol can slow alcohol absorption.
  • Slow down: Reducing your rate of alcohol consumption is a reliable way to avoid alcohol-induced amnesia.
  • Mocktails: Alcohol-free cocktails, or “mocktails,” can be delicious, even healthy alternatives to alcoholic cocktails. There are many websites that provide mocktail recipes.

Finding Treatment for Alcohol Addiction

Alcohol addiction treatment is often the best way to maximize long-term success in recovery. There are many alcohol treatment centers in Washington and Oregon, but they are not all alike. Look for comprehensive programs that can treat every step of recovery, from detox to aftercare.

The Recovery Village Ridgefield is equipped to address every stage of alcohol recovery. Our multidisciplinary team of experts has a proven record of helping people with alcohol use disorders achieve success in recovery. Call today and take the first step toward a healthier future.

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Medical Disclaimer: The Recovery Village aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.