Alcohol poisoning happens when you drink more alcohol than your liver can process, causing your blood alcohol concentration (BAC) to rise to dangerous levels. Your liver breaks down roughly one standard drink per hour, and anything beyond that pace accumulates in your bloodstream. When BAC climbs above 0.31%, breathing can slow or stop entirely, and the risk of death becomes real.
What Counts as Too Much, Too Fast
A standard drink in the United States contains 0.6 ounces (14 grams) of pure alcohol. That’s 12 ounces of regular beer at 5% alcohol, 5 ounces of wine at 12%, or a single 1.5-ounce shot of 80-proof liquor. Many people underestimate how much they’re actually consuming. A strong cocktail can contain two or three standard drinks. A large glass of wine poured at home is often closer to two servings. A high-gravity craft beer at 9% alcohol is nearly double a standard beer.
Because the liver processes alcohol at a fixed rate of about one drink per hour, downing four or five drinks in a single hour means three or four of those drinks are still circulating in your blood, pushing your BAC higher with each sip. Binge drinking, typically defined as four or more drinks within two hours for women or five or more for men, is the most common path to alcohol poisoning. But it doesn’t require a dramatic binge. Someone who rarely drinks can reach dangerous BAC levels on fewer drinks than a heavier drinker would need.
Why Your Body Can’t Keep Up
Your stomach and small intestine absorb alcohol into the bloodstream, and the liver works to break it down. But the liver’s capacity is limited and essentially fixed. It doesn’t speed up because you drank more. Think of it as a bottleneck: alcohol flows in fast, but can only trickle out slowly.
Several factors determine how quickly alcohol hits your bloodstream. Drinking on an empty stomach is one of the biggest. When your stomach is empty, it empties its contents into the small intestine faster, where alcohol absorbs rapidly. Food slows that process, giving the liver more time to keep up. Body size and composition matter too. A smaller person reaches a higher BAC from the same number of drinks. Women generally reach higher BAC levels than men of the same weight, partly because of differences in body water content and how the stomach processes alcohol before it reaches the bloodstream.
People who have had certain weight-loss surgeries face an elevated risk. Procedures that reduce stomach size or bypass parts of the digestive tract accelerate gastric emptying, meaning alcohol reaches the bloodstream faster and produces higher peak BAC levels than the same amount of alcohol did before surgery.
What Happens Inside Your Body
At a BAC between 0.16% and 0.30%, you’ll experience serious impairment: difficulty walking and speaking, confusion, drowsiness, nausea, memory blackouts, vomiting, and possible loss of consciousness. Above 0.31%, alcohol begins interfering with the brain’s ability to regulate basic survival functions.
The most dangerous effect is on breathing. Alcohol is a central nervous system depressant, meaning it slows down brain signals that control automatic processes like respiration. At high enough concentrations, breathing can become irregular, dangerously slow, or stop altogether. Body temperature also drops, because alcohol impairs the brain’s temperature regulation. Severe hypothermia can develop even indoors.
One of the most lethal risks is choking. At very high BAC levels, alcohol suppresses the gag reflex, the automatic response that normally prevents you from inhaling vomit. A person who passes out and vomits can aspirate that vomit into their lungs, blocking their airway. This is a leading cause of death in alcohol poisoning cases, and it can happen silently while someone is unconscious.
Mixing Alcohol With Other Substances
Combining alcohol with other depressants dramatically lowers the threshold for a fatal overdose. Opioid painkillers, benzodiazepines (commonly prescribed for anxiety or sleep), and even some over-the-counter sleep aids all slow down the same brain functions that alcohol targets. Together, their effects don’t just add up; they multiply. Breathing can become dangerously suppressed at BAC levels that would otherwise be survivable on their own. The CDC states plainly that drinking alcohol within a few hours of using opioids or benzodiazepines can make it hard to breathe, damage the brain, and lead to death.
Signs of Alcohol Poisoning
Alcohol poisoning doesn’t always look like what you’d expect. The person may not be stumbling around or acting wild. Often, they’re quiet and still, which is exactly the problem. Key warning signs include:
- Slow or irregular breathing: fewer than eight breaths per minute, or gaps of ten seconds or more between breaths
- Unresponsiveness: you can’t wake the person up, even with shouting or shaking
- Vomiting while unconscious: especially if they don’t wake up during or after
- Cold, clammy, or bluish skin: particularly around the lips and fingertips, signaling poor circulation or low oxygen
- Seizures
- Confusion or stupor beyond normal drunkenness
A common and dangerous mistake is assuming a passed-out person just needs to “sleep it off.” BAC can continue rising for 30 to 40 minutes after the last drink, because alcohol in the stomach and intestines is still being absorbed. Someone who seems okay when they lie down can deteriorate significantly while unconscious.
What Happens at the Hospital
There is no quick antidote for alcohol poisoning. Treatment is supportive, focused on keeping you alive while your body processes the alcohol. Hospital care typically involves monitoring to prevent breathing or choking problems, oxygen therapy if breathing is compromised, IV fluids to prevent dehydration (especially after vomiting), and vitamins and glucose to prevent complications like dangerously low blood sugar or brain damage.
In cases involving methanol or isopropyl alcohol, which are found in products like antifreeze or rubbing alcohol and are sometimes consumed accidentally, hemodialysis may be needed to filter the toxic substances from the blood faster than the body can manage on its own. These types of poisoning are distinct from ethanol (drinking alcohol) poisoning and carry additional risks of blindness and organ failure.
Who Is Most at Risk
Young adults between 18 and 34, particularly college-age drinkers, face the highest risk because binge drinking is most common in this age group. But alcohol poisoning kills people across every demographic. CDC data shows that the rate of accidental alcohol poisoning deaths increased from 0.7 per 100,000 in 2019 to 0.8 in 2020, part of a broader 26% increase in alcohol-induced deaths during that period.
People with lower body weight, those taking medications that interact with alcohol, individuals who rarely drink and have no built-up tolerance, and anyone who has had gastric surgery all reach dangerous BAC levels faster. Tolerance, importantly, does not protect against poisoning. A heavy drinker may feel less impaired at a given BAC, but the alcohol’s effect on breathing, gag reflex, and heart function is just as severe. Feeling “fine” is not the same as being safe.