how to fix a hangover

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A hangover is a collection of unpleasant physical and mental symptoms that occur after a session of heavy alcohol consumption. The severity of hangover symptoms can depend on many factors, such as how much alcohol was consumed and the type of alcohol. But hangovers are caused by only one thing—drinking too much alcohol.

How much is too much? Some people report hangover symptoms after consuming only two or three drinks, while some heavy drinkers never experience hangover symptoms at all. But for most people, the greater the amount of alcohol consumed and the longer the duration of alcohol consumption, the more severe the hangover symptoms.

Common Hangover Symptoms

According to the National Institute on Alcohol Abuse and Alcoholism, a hangover can include some or all of the following symptoms:

Fatigue, weakness, and thirst
Headache and muscle aches
Nausea, vomiting, and stomach pain
Decreased sleep, decreased deep sleep, and increased slow-wave sleep
Vertigo and sensitivity to light and sound
Decreased attention and concentration
Depression, anxiety, and irritability
Tremor, sweating, and increased pulse and blood pressure

Intensity and Duration of Hangover Symptoms

The intensity of these symptoms and the particular set of symptoms can vary from person to person and from occasion to occasion. A person might experience nausea and dizziness on one occasion, but mainly a headache symptoms the next time.

Hangover symptoms usually begin within several hours after the drinking session ends, when blood alcohol concentration (BAC) begins to fall. The symptoms usually peak when BAC returns to zero. Hangover symptoms can last from a few hours to up to 24 hours.

Alcohol Poisoning

Excessive alcohol consumption can cause more than a general feeling of malaise the next day. Extreme alcohol consumption can cause acute alcohol poisoning which can be life-threatening.

The symptoms of alcohol poisoning can include many of the same symptoms as a hangover, but usually more intense and extreme:

Confusion
Difficulty remaining conscious; cannot be awakened when unconscious
Vomiting while unconscious
Slow heart rate and bluish-colored skin
Low body temperature; feels cold to the touch
Seizures
Very slow or irregular breathing

If you see anyone with the above symptoms after drinking, call 911 immediately. Stay with the person and try to turn them on their side so they do not choke on their own vomit. If they stop breathing entirely, begin CPR.

Even if you don't see any of the above symptoms of alcohol poisoning, if the person is passed out and cannot be awakened, they could be at risk of dying. Seek medical help immediately.

When Hangover Symptoms Become a Problem

If you frequently experience hangover symptoms or your hangover symptoms have begun to affect you at school or work, you may have developed an alcohol use disorder. One symptom of alcohol use disorder is continuing to drink in spite of repeated negative consequences.

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National Institute on Alcohol Abuse and Alcoholism. Hangovers. Updated March 2019.
Jung YC, Namkoong K. Alcohol: Intoxication and poisoning - diagnosis and treatment. Handb Clin Neurol. 2014;125:115-21. doi:10.1016/B978-0-444-62619-6.00007-0