A hangover is a collection of signs and symptoms linked to a recent bout of heavy drinking. The sufferer typically has a headache and feels sick, dizzy, sleepy, confused and thirsty.

Hangovers can occur at any time of day, but are usually more common the morning after a night of heavy drinking. As well as physical symptoms, the person may also experience elevated levels of anxiety, regret, shame, embarrassment, as well as depression.

The severity of a hangover is closely linked to how much alcohol was consumed, and whether the sufferer had enough sleep. The less sleep the worse the hangover.

It is impossible really to say how much alcohol can be safely consumed to avoid a hangover. It depends on the individual and factors such as their circumstances that day, how tired they were before they began drinking, whether they were already dehydrated before the drinking began, whether they drank plenty of water during their drinking session and how much sleep they got afterwards.

In the vast majority of cases, hangovers go away after about 24 hours. Responsible drinking can help avoid hangovers.

Causes of a hangover

A hangover is the consequence of having consumed too much alcohol. It is an accumulation of several factors:

  • Urination – alcohol makes people urinate more, which raises the chances of dehydration occurring. Dehydration can give the individual that sensation of thirst and lightheadedness.
  • Immune system response – there may be an inflammatory response by the immune system to alcohol, which may affect appetite, concentration and memory.
  • Stomach irritation – alcohol consumption raises the production of stomach acids; it also slows down the rate at which the stomach empties itself – this combination can lead to nausea, vomiting or stomachache.
  • Drop in blood sugar – some people’s blood sugar levels can fall steeply when they consume alcohol, resulting in shakiness, moodiness, tiredness, general weakness, and even seizures in some cases.
  • Dilation of blood vessels – alcohol consumption can cause the blood vessels to dilate (widen), which can cause headaches.
  • Sleep quality – although sleeping when drunk is common, the quality of that sleep may be poor. The individual may wake up tired and still sleepy.
  • Congeners – these are substances that are produced during fermentation and are responsible for most of the taste and aroma in distilled drinks (whisky, gin, etc). They are known to contribute to symptoms of a hangover. Examples of congeners include esters and aldehydes.

A symptom is something the sufferer or patient feels and describes, such as feeling thirsty or a headache, while a sign is something everybody, including the doctor or nurse can detect, such as bloodshot eyes, or a rash.

The signs and symptoms of a hangover generally start to occur when the drinker’s blood alcohol drops considerably – typically, the morning after a night of high alcohol consumption, and may include:

  • Accelerated heartbeat
  • Anxiety
  • Bloodshot eyes
  • Body and muscle aches
  • Diarrhea
  • Dizziness
  • Halitosis (bad breath)
  • Headache
  • Hypersalivation
  • Flatulence
  • Lethargy, tiredness, fatigue, listlessness
  • Nausea
  • Photophobia (sensitivity to light)
  • Problems focusing or concentrating
  • Sensitivity to loud sounds
  • Depression (dysphoria)
  • Irritability
  • Moodiness
  • Stomachache
  • Thirst
  • Trembling or shakiness, erratic motor functions
  • Vomiting

If the individual has the following more severe signs and symptoms, they may have alcohol poisoning – this is a medical emergency and medical help should be sought as soon as possible:

  • Breathing loses its regular rhythm
  • Breathing slows down to less than eight inhalations per minute
  • Confusion or stupor. The patient is in a daze
  • Fits (seizures)
  • Hypothermia – body temperature drops
  • The patient passes out (loses consciousness)
  • The skin becomes pale, or takes on a blue tinge
  • Vomiting continues and does not abate.

There is no “treatment” for a hangover – the best way to avoid one is either not to drink, or to drink sensibly and within the recommended limits. Men should not consume over 3 to 4 units and women 2 to 3 units of alcohol per day. You should not drink more than you know your body can handle.

A hangover has to run its course, and that can be best done with rest, drinking plenty of water, perhaps some painkillers and simply waiting.

Do not go for a “hair of the dog” – an alcoholic drink to get rid of a hangover. This is a myth, and will likely just prolong your hangover symptoms.

The following tips may help:

  • Drink – sip water throughout the day. Water is the best fluid.
  • Eating – go for bland foods, such as crackers or bread, which may raise blood sugar and are easy on the stomach. Fructose-containing foods may help metabolize (break down and get rid of) the alcohol more rapidly.
  • Pain – some people may take a painkiller. Be aware that certain painkillers, such as acetaminophen (Tylenol, paracetamol) attack the liver, while aspirin may not be ideal for a very delicate stomach. If you are not sure what to choose, ask a qualified pharmacist or health care professional.
  • Rest – if you can manage to get back to sleep, you will probably recover a little bit faster. Make sure you have some water next to your bed.

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