Hangover

A hangover encompasses the constellation of symptoms experienced after excessive consumption of ethanol. It excludes acute ethanol poisoning, and implies that the ethanol has completely or fully been metabolized. While there is much folklore about the cause and treatment, the actual mechanisms have not been researched extensively, and probably vary among individuals.

Common symptoms include headache, thirst, nausea, fatigue, increased sensitivity to light and noise, and irritated eyes. There may be a craving for more alcohol.

Mechanisms include those caused directly by metabolizing ethanol, alcohol withdrawal in habituated persons, and toxic byproducts of alcohol metabolism. Metabolizing alcohol can cause:

• Dehydration
• Electrolyte imbalance
• Gastrointestinal disturbances
• Low blood sugar
• Sleep and biological rhythm disturbances

Acetaldehyde is the most likely toxic metabolite, although genetic enzyme deficiencies may cause high levels of other products of metabolism.

Compounds other than ethanol, both for flavoring and toxic additives such as methanol, can contribute to a hangover, as well as other drugs taken with the alcohol, especially nicotine. Personality type and family history of alcoholism may contribute, although it has been reported that heavy drinkers are less likely to have hangovers.