Alcohol poisoning happens when you drink faster than your body can process the alcohol, causing it to build up in your bloodstream to dangerous levels. Your liver breaks down alcohol at a fixed rate of roughly one standard drink per hour, and it cannot speed up no matter how much you’ve consumed. Every drink beyond that rate stays circulating in your blood, and if enough accumulates, it begins shutting down the parts of your brain that control breathing, heart rate, and body temperature.
What Happens Inside Your Body
Alcohol works by altering two key brain chemicals that have opposite jobs. One calms your brain and body, and alcohol amplifies its effects. The other stimulates your brain and body, and alcohol suppresses it. At low doses, this is why a drink or two can make you feel relaxed and less alert. At dangerously high doses, this same mechanism overshoots: your brain becomes so sedated that it can no longer manage the automatic functions keeping you alive.
Breathing slows or becomes irregular. Heart rate drops. Body temperature falls. Your gag reflex, which normally protects you from choking, stops working properly. This is the core danger of alcohol poisoning: it’s not a stomachache or a bad hangover, it’s your central nervous system losing the ability to run your body’s most basic operations.
How Much Alcohol It Takes
There’s no single number of drinks that causes alcohol poisoning in every person, but the pattern that leads to it is well defined. Binge drinking, consuming five or more drinks for men or four or more for women in about two hours, raises blood alcohol concentration to 0.08% or higher. Alcohol poisoning typically occurs well above that threshold, when someone continues drinking heavily past the point of legal intoxication.
One standard drink in the United States contains about 14 grams of pure alcohol. That’s roughly one 12-ounce beer, one 5-ounce glass of wine, or one 1.5-ounce shot of liquor. But many real-world drinks contain far more alcohol than a single standard serving. A strong cocktail might count as two or three standard drinks. A large glass of wine poured at home is often closer to two servings. This mismatch between what people think they’re drinking and what they’re actually consuming is one of the most common ways alcohol poisoning happens without anyone expecting it.
Because the liver processes only about one drink per hour, someone who takes six shots in 30 minutes has roughly five drinks’ worth of alcohol still circulating with nowhere to go. The unmetabolized alcohol keeps building in the blood even after the person stops drinking, which is why someone can seem “just drunk” and then deteriorate significantly over the next hour.
Risk Factors That Lower the Threshold
Your body size matters. A smaller person reaches dangerous blood alcohol levels with fewer drinks than a larger person, because alcohol distributes through body water, and there’s simply less of it in a smaller frame. Drinking on an empty stomach also speeds absorption. Food in your stomach slows the rate at which alcohol enters your bloodstream, though it won’t prevent poisoning during heavy drinking.
Mixing alcohol with other substances that sedate the central nervous system is especially dangerous. Combining alcohol with certain prescription sedatives lowers the fatal threshold by as much as 20%, meaning a blood alcohol level that might not be lethal on its own becomes lethal when paired with another depressant. Prescription painkillers carry a similar risk. The combined sedative effect on breathing can be greater than either substance alone.
Overall health, tolerance level, and how quickly you’re drinking all play a role. Someone who rarely drinks can reach dangerous levels faster than someone whose body has adapted to regular alcohol exposure, though tolerance does not protect against poisoning. It just delays some of the warning signs.
Signs That Someone Is in Danger
The symptoms of alcohol poisoning look different from being very drunk. Watch for slow or irregular breathing, skin that looks pale or bluish, a body temperature that feels unusually cold, confusion so severe the person can’t respond to you, vomiting while unconscious or semiconscious, and seizures. A person who has passed out and cannot be woken up is not “sleeping it off.” Their blood alcohol level may still be rising from drinks absorbed in the stomach.
Choking on vomit is one of the most common ways alcohol poisoning kills. When the gag reflex is suppressed, vomit can enter the airway and block breathing entirely. This can happen silently while someone appears to be sleeping.
What Alcohol Poisoning Can Do to the Body
Even when someone survives, the damage can be lasting. Severe dehydration from repeated vomiting can trigger seizures or cause permanent brain damage. If breathing slows enough to deprive the brain of oxygen for even a few minutes, the resulting injury can be irreversible. Vomit that enters the lungs can cause a serious infection called aspiration pneumonia, which requires hospitalization on its own.
The brain is particularly vulnerable. Oxygen deprivation during alcohol poisoning can destroy brain cells that don’t regenerate, leaving survivors with lasting cognitive problems, memory loss, or impaired motor function.
What to Do If Someone Shows These Signs
Call emergency services immediately. While waiting, keep the person sitting up or lying on their side so that if they vomit, it drains out of their mouth rather than back into their airway. Cover them with a blanket, since alcohol poisoning drops body temperature. Stay with them and talk to them calmly, explaining what you’re doing, because disorientation can make people combative even when they need help. When paramedics arrive, tell them as much as you can about how much the person drank, what they drank, whether they took any other substances, and when they last seemed conscious and responsive.
Do not try to make them vomit, give them coffee, put them in a cold shower, or let them “sleep it off.” None of these reverse alcohol poisoning, and several of them, particularly unsupervised sleep and induced vomiting, can make the situation more dangerous.