Most hangovers feel miserable but resolve on their own within 24 hours. You should go to the hospital if you notice any signs that cross the line from a normal hangover into alcohol poisoning, severe dehydration, or another medical emergency. The key red flags are slow or irregular breathing (fewer than 8 breaths per minute, or gaps longer than 10 seconds between breaths), seizures, an inability to stay conscious, confusion beyond typical grogginess, and skin that looks blue, gray, or unusually pale.
A standard hangover brings headache, nausea, fatigue, muscle aches, and thirst. These symptoms peak when your blood alcohol level drops to near zero, typically the morning after drinking. If what you’re experiencing goes beyond that list, or if symptoms are getting worse instead of better as hours pass, something more dangerous may be happening.
Alcohol Poisoning vs. a Bad Hangover
A hangover is your body recovering after it has already processed most of the alcohol. Alcohol poisoning, by contrast, happens while alcohol is still flooding your system at dangerous levels. It can suppress your breathing, heart rate, body temperature, and gag reflex. In severe cases, it leads to coma and death.
The distinction matters because alcohol poisoning can still be present the morning after drinking. Your blood alcohol level can continue rising even after you stop drinking, especially if you consumed a large amount in a short window. Someone who “seems fine” when they fall asleep can deteriorate overnight. If you find someone the next morning who is difficult to wake, breathing slowly, or vomiting while unconscious, that is not a hangover. Call 911 immediately.
Symptoms that always warrant a 911 call:
- Slow or irregular breathing: fewer than 8 breaths per minute, or gaps longer than 10 seconds between breaths. Normal breathing runs 12 to 20 breaths per minute.
- Seizures: full-body convulsions that can occur during acute intoxication or as alcohol leaves the system.
- Unresponsiveness: you cannot wake the person with loud shouting or by firmly pinching their arm.
- Confusion or incoherence: beyond simple tiredness, the person cannot answer basic questions or recognize where they are.
- Vomiting while unconscious: this creates a choking risk, even if the person seems to be “sleeping it off.”
- Cold, clammy, or discolored skin: blue, gray, or very pale skin (including lips and nail beds) signals dangerously low oxygen or body temperature.
Severe Dehydration From Vomiting
Alcohol is a diuretic, meaning it pulls water out of your body faster than normal. Add repeated vomiting on top of that, and you can become seriously dehydrated. A mild hangover with occasional nausea is manageable at home with small sips of water or an electrolyte drink. But if you cannot keep any fluids down for several hours, the situation changes.
Signs of dehydration that need medical attention include dry lips and mouth despite drinking water, producing very little or no urine, feeling unusually dizzy or lightheaded when you stand, a rapid heartbeat, and extreme irritability or confusion. The Mayo Clinic recommends contacting a healthcare provider if you’ve been unable to keep fluids down or have had persistent diarrhea for 24 hours or more. In those cases, you likely need intravenous fluids to rehydrate safely, something only a hospital or emergency room can provide.
Blood in Your Vomit
Forceful or repeated vomiting can tear the lining where your esophagus meets your stomach. This is called a Mallory-Weiss tear, and its hallmark sign is vomiting blood, which may look bright red or resemble dark coffee grounds. Some people also notice dark, tarry stools, which indicate blood passing through the digestive tract.
Most of these tears heal on their own, but significant blood loss can cause dizziness, fainting, a racing pulse, or pale skin. If you see blood in your vomit after heavy drinking, go to the emergency room. In rare cases the tear can deepen through the full wall of the esophagus, which requires emergency surgery.
Low Blood Sugar
Alcohol interferes with your liver’s ability to release stored sugar into your bloodstream. After a night of heavy drinking, your blood sugar can drop low enough to cause symptoms that mimic or worsen a hangover: shakiness, confusion, a fast heartbeat, drowsiness, slurred speech, and intense nausea. If blood sugar falls below about 70 mg/dL, you’re in hypoglycemic territory.
What makes this dangerous is the overlap with hangover symptoms. You might assume you’re just hungover when your brain is actually starving for fuel. Severe hypoglycemia without treatment can lead to loss of consciousness, seizures, and coma. If someone who has been drinking heavily becomes increasingly confused, uncoordinated, or difficult to rouse, low blood sugar is one possible cause, and they need emergency care.
Heart Rhythm Problems
Binge drinking can trigger an abnormal heart rhythm even in people with no history of heart disease. This is sometimes called “holiday heart” because it tends to appear after celebratory drinking. The most common rhythm disturbance is a fast, irregular heartbeat that may come with chest tightness, shortness of breath, lightheadedness, or feeling like you might faint.
A hangover can make your heart beat a bit faster than usual, and that alone isn’t cause for alarm. But if you feel your heart racing or fluttering in a way that feels distinctly wrong, if you have chest pain, or if you nearly pass out, those are signs of a rhythm problem that needs evaluation. Alcohol poisoning itself can also cause the heart to beat irregularly, and a dangerously low body temperature from alcohol exposure can lead to cardiac arrest.
Seizures
Seizures related to alcohol can happen in two different scenarios. During acute intoxication, extremely high blood alcohol levels can overwhelm the brain. More commonly, seizures strike as alcohol leaves the system, particularly in people who drink heavily and regularly. These withdrawal seizures tend to appear 6 to 48 hours after the last drink and present as full-body convulsions.
Up to one-third of people going through significant alcohol withdrawal experience seizures. While many are brief and self-limiting, they can progress to a prolonged state that becomes life-threatening. Any seizure after heavy drinking is a reason to call 911, even if the person seems to recover quickly afterward.
Dark or Cola-Colored Urine
If your urine looks like dark tea or cola the day after drinking, this could be more than dehydration. Heavy alcohol use can cause muscle tissue to break down, a condition called rhabdomyolysis. Damaged muscle fibers release their contents into the bloodstream, which can overwhelm the kidneys. The classic trio of symptoms is unexpectedly severe muscle pain, dark urine, and profound weakness or fatigue.
Rhabdomyolysis is treatable, but early diagnosis makes a significant difference in preventing permanent kidney damage. If your urine is noticeably brown or you have muscle pain that seems far worse than a typical hangover, get to an emergency room.
What Happens at the Hospital
If you do go to the ER for an alcohol-related emergency, the treatment is largely supportive. Doctors focus on stabilizing what alcohol has disrupted. The most common intervention is intravenous fluids to correct dehydration and restore electrolyte balance. If blood sugar is low, you’ll receive a glucose solution through the IV. Your heart rhythm, breathing, oxygen levels, and temperature will be monitored continuously.
For alcohol poisoning specifically, doctors protect your airway and keep you breathing safely while your body processes the remaining alcohol. There is no medication that speeds up how fast your body clears alcohol. Older interventions like stomach pumping are generally avoided in alcohol cases. The hospital stay may last several hours or overnight, depending on how your body responds. For gastrointestinal bleeding, doctors may perform an endoscopy to locate and treat the source. For suspected rhabdomyolysis, blood tests will check for muscle breakdown markers and kidney function.
The bottom line is straightforward: a normal hangover makes you feel terrible, but it improves steadily throughout the day. If symptoms are worsening, if you can’t keep water down for hours, if breathing is slow or erratic, if there’s blood in the vomit, if the person can’t be woken up, or if anything feels genuinely frightening, err on the side of calling 911. The risks of going to the hospital unnecessarily are zero. The risks of waiting too long are not.