The term hangover is most commonly used to describe the symptoms you may experience after drinking a large amount of alcohol.

Most people get hangover symptoms after drinking large quantities of alcohol, even those who are not generally considered to be heavy drinkers.

It may be dangerous to drive or operate heavy machinery whilst hung over, even if your blood alcohol level is under the legal limit. The maximum blood alcohol level permitted by law when driving is 80mg per 100ml of blood, but it is safer to avoid alcohol at all if you intend to drive within the next 24 hours.

Hangovers have social as well as health costs. Employers lose thousands of work hours every year to staff who take sick days, or whose work performance is affected, due to hangovers. Heavy drinkers can show violent tendencies and personal relationships may suffer as a result.

Causes

Alcohol acts as a diuretic and leads to dehydration, which causes many of the symptoms associated with a hangover. Diuretics increase the amount of urine produced by encouraging the removal of salts such as potassium and sodium (salt) from the blood. As a result, an increased amount of water is drawn out of the blood and into the kidneys, where it is passed out through the urine.

Alcohol can also cause malnutrition because it uses it the body’s store of vitamins and minerals and reduces blood sugar levels. Together with dehydration, this can be responsible for the throbbing headache you may experience with a hangover. Alcohol can also cause blood vessels in the head to dilate, adding to the pain of a hangover headache.

Treatment

Treatment of hangovers involves rehydrating the body and dealing with the painful symptoms.

Over-the-counter analgesics will help to cope with the pain of headaches and muscle cramps. Paracetamol-based remedies are preferable as aspirin may further irritate the stomach and increase nausea and sickness.

There is evidence to suggest that fructose, a natural sugar found in fruit juice and honey, helps the body to process alcohol faster. Bouillon soup, a thin vegetable-based broth, is also a good source of vitamins and minerals (including salt and potassium), to top up the body’s depleted resources.

Alcohol causes dehydration, as the body loses salt and minerals. You can replace these by drinking plenty of bland liquids such as water and soda water. Some isotonic drinks are now available in most shops, which replace lost salt in the body.