Alcohol Poisoning vs. Being Drunk: How to Spot the Emergency

The call I dread most in clinical work is the one that comes after someone “slept it off.” Most patients who die from alcohol poisoning are found hours after someone decided not to call for help because they thought the person just needed to sleep. The signs were there. No one knew what they were looking at. That is the gap this guide is meant to close.

What Actually Happens to Your Body When You Drink

Every drink you take puts ethanol into your bloodstream. Your liver metabolises it using an enzyme called alcohol dehydrogenase, or ADH, converting ethanol into acetaldehyde. Acetaldehyde is then broken down further by aldehyde dehydrogenase, ALDH2, into acetate, which your body clears relatively harmlessly.

The problem is capacity. Your liver can process roughly one standard drink per hour under normal conditions. Drink faster than that and ethanol accumulates in your blood. Your blood alcohol concentration, or BAC, rises. Most of what people recognise as “being drunk” happens as BAC climbs from 0.02% to around 0.15%.

Above 0.20%, alcohol starts suppressing the brainstem. That is where breathing, heart rate, and the gag reflex are controlled. This is where drunk stops and poisoned begins.

Being Drunk: What Normal Intoxication Actually Looks Like

A drunk person is impaired, but their body is still running its essential functions. The typical presentation includes slurred speech, reduced coordination, slowed reaction time, lowered inhibitions, and sometimes nausea. Judgment is impaired and emotional responses are amplified, either toward euphoria or irritability depending on the person and the setting.

Vomiting can occur and is actually a protective reflex at moderate intoxication levels. The gag reflex is still working. The person is still responsive to voice and touch. They can usually tell you their name, follow a simple instruction, or hold a conversation even if poorly.

None of that means drunk is harmless. Falls, accidents, aggression, and risky decisions cause real harm at intoxication levels well below the threshold for poisoning. But a drunk person who is coherent and conscious is not in immediate mortal danger from the alcohol itself.

Alcohol Poisoning Symptoms: The Signs That Mean Call Emergency Services Now

Alcohol poisoning presents differently. The brain is not just impaired. It is being shut down by a chemical at toxic concentration.

The clinical picture of alcohol poisoning includes severe confusion or complete unresponsiveness, dangerously slow or irregular breathing, hypothermia (core body temperature dropping below 35 degrees Celsius), cyanosis, and loss of the gag reflex. That last one matters most. When the gag reflex goes, vomit can enter the lungs and cause death by aspiration even if the person is still breathing.

Why BAC Can Keep Rising After Someone Stops Drinking

This is the piece most people miss. Alcohol in the stomach continues absorbing into the bloodstream after the last drink. A person can stop drinking, appear to plateau, then deteriorate sharply 30 to 90 minutes later as alcohol from the gut catches up to the blood.

This is why “they were fine when I checked on them 20 minutes ago” is not a reliable safety signal. BAC is not a static number. It keeps moving.

BAC and What It Actually Does at Each Level

BAC is measured as the percentage of ethanol in the blood by volume. Legal driving limits in most countries sit at 0.05% to 0.08%, which is a level where coordination and judgment are already impaired.

These are averages. A person who rarely drinks can reach dangerous impairment at a lower BAC than someone with high alcohol tolerance. Understanding how tolerance builds over time matters here, and it can create false confidence in people who drink regularly.

How Alcohol Suppresses the Brainstem and Why That Kills

Ethanol is a central nervous system depressant. It works primarily by enhancing GABA-A receptor activity and inhibiting NMDA glutamate receptors. GABA is the brain’s main inhibitory signal. When you amplify it artificially with alcohol, you slow everything down, including the automatic processes you do not consciously control.

The brainstem controls three functions critical to staying alive: respiratory drive (the automatic signal to breathe), the gag reflex (which stops you from inhaling vomit), and thermoregulation (maintaining a safe core temperature). At toxic BAC levels, all three start to fail.

Respiratory depression is the most common cause of death in alcohol poisoning. The drive to breathe slows. Carbon dioxide builds up. Oxygen drops. Without intervention, the person stops breathing entirely. This can happen while they appear to simply be “sleeping deeply.”

What to Do If You Suspect Alcohol Poisoning

Act, do not wait. The instinct to hope someone sleeps it off costs lives.

Put the person in the recovery position if they are unconscious: on their side, with their top knee bent forward to keep them stable and their airway open. This position means that if they vomit, it drains out rather than into their lungs. Never leave them on their back.

Call emergency services immediately. Tell the dispatcher the person is unconscious or cannot be woken, describe their breathing, and give your location. Stay on the line.

Do not give them coffee or water to “sober them up.” Coffee does not accelerate alcohol metabolism. It just creates an alert, intoxicated person. Time and liver function are the only mechanisms that clear alcohol from the blood.

Do not let them “sleep it off” without monitoring. If you are not checking breathing every 10 minutes, you are not monitoring. You are leaving them.

Alcohol Poisoning Risk Factors: Who Is Most Vulnerable

Not everyone reaches poisoning at the same intake level. Body weight affects how much blood ethanol is diluted into. Biological sex affects the ratio of ADH enzyme activity and body water content, which is why women typically reach higher BAC than men at the same intake. Age matters because liver enzyme activity changes with age.

The genetic variant ALDH22, found in roughly 30 to 50% of East Asian populations, reduces the efficiency of the second stage of alcohol metabolism. People carrying this variant accumulate acetaldehyde faster, which causes flushing, nausea, and rapid heart rate, but does not protect against alcohol poisoning.

Mixing alcohol with other CNS depressants dramatically lowers the threshold for dangerous respiratory suppression. Benzodiazepines, opioids, sleep medications, and antihistamines all compound the respiratory depression effect of ethanol. This combination is particularly dangerous and accounts for a significant proportion of overdose deaths where alcohol is a contributing factor. The interaction between alcohol and certain substances can accelerate toxicity in ways that surprise even experienced drinkers.

The “Just Sleeping It Off” Myth and Why It Gets People Killed

Most preventable deaths from alcohol poisoning happen because someone made a decision to not call for help. The reasoning is usually one of three things: “They are fine, just drunk.” “I do not want to get them in trouble.” “I do not want to call and be wrong.”

All three are understandable. None of them are worth a life.

The practical reality is that emergency responders and hospital staff are not there to judge. They are there to keep someone alive. In many places, Good Samaritan laws exist specifically to protect people who call for help in an overdose situation. The fear of consequences should not be the deciding factor when someone is unresponsive.

Binge Drinking and the Risk of Accidental Poisoning

The CDC defines binge drinking as a pattern of drinking that raises BAC to 0.08% or above, typically five or more drinks for men or four or more for women within about two hours. Binge drinking is the direct mechanism behind most cases of alcohol poisoning because it overwhelms the liver’s processing capacity in a short time window.

Drinking games, shots in rapid succession, and drinking on an empty stomach all accelerate BAC rise. Carbonated mixers speed gastric emptying, which means alcohol gets to the small intestine (where absorption is fastest) more quickly.

Approximately 2,200 people die from alcohol poisoning in the United States each year according to the CDC. The majority are adults aged 35 to 64, which contradicts the assumption that this is purely a problem for younger, inexperienced drinkers.

Long-Term Drinking and Tolerance: A Hidden Risk Factor

People who drink heavily over years develop alcohol tolerance through several mechanisms, primarily involving ADH upregulation and changes in GABA-A receptor sensitivity. The result is that they can appear functional at BAC levels that would incapacitate a lighter drinker.

This creates a dangerous disconnect. A high-tolerance drinker may not appear “that drunk” to observers, even when their BAC is approaching dangerous levels. The absence of obvious impairment is not a reliable safety indicator. For people curious about how the liver handles heavy long-term alcohol load, the science of alcohol metabolism explains why tolerance and toxicity are not opposites.

If alcohol poisoning, binge drinking episodes, or an inability to control intake are recurring patterns rather than one-off events, that warrants clinical attention. The DSM-5 defines Alcohol Use Disorder across a spectrum from mild to severe, based on criteria including loss of control over intake, continued use despite harm, increasing tolerance, and withdrawal symptoms when not drinking. Recurrent situations involving high-risk drinking, including episodes close to or at poisoning threshold, are themselves a DSM-5 criterion.

At Phuket Island Rehab, we work with people across that full spectrum, from those questioning their drinking to those whose health has already been significantly affected. Treatment is medically supervised, individualised, and structured for people coming from across Asia and internationally. If you are recognising a pattern in yourself or someone close to you, a direct conversation with our clinical team is a practical starting point, not a commitment.

Alcohol poisoning and being drunk exist on the same physiological continuum but cross a clinical threshold when ethanol levels suppress brainstem function. The key markers that separate dangerous poisoning from ordinary intoxication are: unresponsiveness to voice and touch, breathing rate below 8 per minute or with long pauses, absent gag reflex, cyanosis, hypothermia, and seizures. BAC can continue to rise after drinking stops, which means a person who appears stable can deteriorate rapidly. The underlying mechanism is ethanol’s enhancement of GABA-A receptor activity combined with NMDA inhibition, which slows and eventually stops the automatic brainstem signals that keep someone breathing.

The practical takeaway is simple: if you are not sure whether someone is dangerously poisoned or just drunk, treat it as poisoning. Put them in the recovery position, call emergency services, and stay with them. Do not give coffee, do not let them sleep unmonitored, and do not assume that prior tolerance means they are safe. People with high tolerance can reach fatal BAC without appearing severely impaired. The cost of calling for help unnecessarily is minimal. The cost of not calling when it was necessary is final.

As John A. Smith of Phuket Island Rehab puts it: “Every week in clinical practice I see the damage that comes from someone waiting too long. The patients who come to us after a poisoning event often say the same thing: they thought the person would be fine. The ones who call immediately are the reason their friend is still alive.”

What is the difference between alcohol poisoning and being drunk?

Being drunk means your blood alcohol concentration is high enough to impair coordination, speech, and judgment, but your body is still managing its essential functions. Alcohol poisoning means BAC has reached a level that suppresses brainstem activity, threatening breathing, body temperature regulation, and the gag reflex. The clinical threshold is roughly 0.20% BAC and above, though individual factors mean some people can be in danger below that level. The clearest distinction is responsiveness: a drunk person can be roused; someone with alcohol poisoning cannot.

Can you die from alcohol poisoning while sleeping?

Yes, and this is exactly how most alcohol poisoning deaths occur. Respiratory depression caused by high BAC can slow breathing to the point where it stops entirely, and this can happen with no external warning signs. A person who appears to be sleeping deeply may actually have dangerously suppressed brainstem activity. Check breathing rate and responsiveness regularly. If you cannot rouse them and breathing is slow or irregular, call emergency services immediately.

How much alcohol does it take to cause alcohol poisoning?

There is no single number because body weight, sex, age, drinking history, and whether food was in the stomach all affect how quickly BAC rises. As a clinical benchmark, a BAC of 0.20% or above starts to enter dangerous territory, and 0.35% and above carries a serious risk of coma and death. For a 60kg person with low tolerance drinking on an empty stomach, six to eight standard drinks in two hours can approach that range. Drinking games, shots taken in rapid succession, and mixing alcohol with other depressants all increase risk significantly.

What should I do if someone passes out after drinking?

Place them immediately in the recovery position: on their side, top knee pulled forward to stabilise them, head tilted back slightly to keep the airway open. Call emergency services. Do not leave them on their back, as this allows vomit to be inhaled if the gag reflex fails. Do not try to “wake them up” with coffee or food. Stay with them, monitor breathing every few minutes, and be ready to perform CPR if breathing stops. If you cannot rouse them at all, that is a medical emergency regardless of what else you observe.

Is alcohol poisoning more common in people who drink regularly?

Regular heavy drinkers are not protected from alcohol poisoning. Alcohol tolerance means they may show fewer visible signs of impairment at BAC levels that are already dangerous, which can lead both the person and those around them to underestimate the risk. The CDC data on alcohol poisoning deaths shows the majority occur in adults aged 35 to 64, many of whom drink regularly. Tolerance is a neurological adaptation, not a safety mechanism. It does not prevent the brainstem depression that causes poisoning at high enough BAC.

Can alcohol poisoning happen if someone stops drinking?

Alcohol in the stomach continues absorbing into the bloodstream for up to 90 minutes after the last drink. A person who appears to have stabilised can deteriorate significantly as this remaining alcohol reaches the blood. This is a critical and often missed risk window. Someone who seemed “okay” at midnight can be in serious danger at 1:30am without having consumed another drink. This is why ongoing monitoring matters even after drinking has stopped.

What is the recovery position and why does it matter for alcohol poisoning?

The recovery position places an unconscious person on their side so that if they vomit, the fluid drains out of their mouth rather than into their airway. This directly prevents aspiration, which is one of the main causes of death in alcohol poisoning when the gag reflex is absent or impaired. Roll the person onto their side, bend the top knee forward to keep them from rolling back, tilt the head back to open the airway, and place their top hand under their cheek to maintain head position. This position should be maintained until emergency services arrive.