Last Updated on October 15, 2021
Blackouts are a common side effect of excessive drinking, and binge drinking in particular. But why do they occur? What is the science behind blackouts, who is more likely to get them, and how can you stop them from happening?
We’ll address all of this and more below. But first, an “alcohol blackout” definition:
What Does “Alcohol Blackout” Mean?
You may have had particularly too much to drink one night. You might remember starting the evening with a few drinks, maybe feeling a good buzz…and that’s it. Nothing else. Just empty space until you woke up feeling sick the morning after. Perhaps you remember some snippets, or have pictures or stories from your friends, but you simply have no recollection of what happened while you were drunk. Sound familiar?
This is termed a “blackout”—a span of time when you were awake and doing things, but remember nothing due to the effects of alcohol. While this is common among people addicted to alcohol, it can happen to anyone who drinks a large amount in a short window of time. In fact, many college-aged people have stories about that time they “blacked out.”
What Causes Blackouts When Drinking?
Alcohol is a central nervous system (CNS) depressant, which means it reduces the activity of your neurons—AKA brain cells. This effect increases with higher quantities of alcohol. In small or moderate doses, this effect can be pleasant: you might feel relaxed, a little loosened up, or both. This is commonly referred to as “buzzed.”
Drinking more might cause you to feel “tipsy.” You may feel warm, and even a little silly. Those who continue drinking past this will generally feel drunk: their speech is slurred and rambling, movements are sluggish, and they may be numb to pain or temperature. Drinking even more at this stage is usually how people “black out”—they lose their memory past this point, and may even pass out depending on how much they drink.
How Alcohol Affects Your Brain & Memory
Why do the effects of drinking alcohol usually occur in this order? It has to do with which parts of your brain the alcohol impacts first.
The effects of alcohol start at the frontal lobe, which controls your personality and decision-making. By inhibiting some of your frontal lobe’s social restraints—nervousness around someone you like, for example—you may feel loosened up and a little cheerier. Hence the term “liquid courage.”
If you drink more, the motor and sensory cortexes behind your frontal lobe are the next to be inhibited. This results in clumsier movements and speech, and explains why people who are drunk are less sensitive to pain.
But why do you black out when you drink alcohol? This happens when you have enough booze in your system to inhibit your hippocampus—the part of your brain that creates and stores memories. With this area disabled, you may not record anything that happens. The events of the night before will seem to have been erased.
Note that just because someone might be blacked out—so drunk that they won’t remember what happened—doesn’t mean they are unconscious. Many people are capable of complex tasks while blacked out, such as vandalism or even driving a car. And this is what makes blacking out so dangerous. To reach this stage, you must be at a very advanced level of intoxication—enough so that you might endanger your own well-being.
How To Stop Blacking Out When Drinking
The best way to not black out when drinking is to limit your consumption. Blackouts typically occur once you are significantly intoxicated. If you stick to just a few drinks, your memory will generally be fine.
However, there are certain drugs that can make the effects of alcohol more extreme, increasing your risk. CNS depressants like Valium or Ambien can reduce your brain activity faster when taken with alcohol, potentially causing blackouts without much drinking. If you take these or other similar medications, be especially careful around alcohol, or even skip drinking completely.
Blacking out certainly isn’t healthy—you must consume large amounts of alcohol to black out, which is hard on your liver and brain. Plus, blacked out people may engage in dangerous behavior—drunk driving, unsafe sex, or drinking even more—without being aware of it. If you notice that this happens to you often, there are steps you can take to limit your consumption and slow the effects of alcohol, including:
- Spacing your drinks, or alternating with water
- Eating a full meal before drinking
- Staying hydrated
- Setting a drink limit before you begin, and asking a friend to help you stick to it
If you still find it hard to control your drinking in social situations, or you are concerned by the impact that blackouts are having on your life, there are new ways of getting help. Online programs like Ria Health can help you cut back or quit from home, without having to put your life on hold. We offer access to weekly coaching meetings, anti-craving medications, digital support groups, and more—all from your smartphone.
- Costardi J V V et al. A review on alcohol: from the central action mechanism to chemical dependency. Rev Assoc Med Bras. 2015 Aug; 61(4): 381-7. Accessed December 22, 2020
- Moselhy H F et al. FRONTAL LOBE CHANGES IN ALCOHOLISM: A REVIEW OF THE LITERATURE Alcohol and Alcoholism. 2001 Sept; 36(5): 357–368. Accessed December 22, 2020
- Science Daily. The biology behind alcohol-induced blackouts. Accessed December 22, 2020
- White A M et al. Prevalence and Correlates of Alcohol-Induced Blackouts Among College Students: Results of an E-Mail Survey. Journal of American College Health. 2002; 51(3): 117-131. Accessed December 22, 2020
- Tanaka E. Toxicological interactions between alcohol and benzodiazepines. J Toxicol Clin Toxicol. 2002; 40(1): 69-75. Accessed December 22, 2020
- Zosel A et al. Zolpidem misuse with other medications or alcohol frequently results in intensive care unit admission. Am J Ther. 2011 Jul; 18(4): 305-8. Accessed December 22, 2020
- Oscar-Berman M et al. Alcoholism and the Brain: An Overview. Alcohol Res Health. 2003; 27(2): 125–133. Accessed December 22, 2020