One of the oldest hangover cures is the “hair of the dog”. It’s an idea that can be traced all the way back to the time of Aristophanes, and the theory goes that in order to overcome the pain caused by alcoholic drinks the evening before, you take a swig of it the next day. But does the hair of the dog actually work?
Somehow, this expression has stood the test of time, and you’ll regularly catch bar-goers stopping off for one more drink the day after a binge. In fact, we’ve probably all tried it at some point – with varying degrees of success.
As you may imagine, drinking on top of drinking is no good for your body. We all know that consuming more water may be the smartest thing here, but if you’ve managed to drink enough alcohol to result in a hangover and are looking for a quick-fix, will a pint cut it? Or is the hair of the dog really just an old wives' tale we’ve been convinced by?
A hangover develops when an elevated concentration of alcohol in the blood caused by drinking falls sharply after drinking stops. The symptoms -- usually some combination of headache, thirst, fatigue, dizziness, nausea and general grumpiness -- reach their peak when the blood-alcohol level hits zero.
The “hair of the dog” hangover cure has not been well-studied, but a few theories exist as to why it may help you feel better the morning after heavy drinking.
#1. Metabolism of Alcohol Congeners
Chemicals called congeners, which are present in varying amounts in different alcoholic beverages, contribute to the severity of hangover symptoms.1 For example, methanol is a congener found in beer and wine.
In other words, booze contains trace amounts of methanol, which the body breaks down into formaldehyde about a day after consumption, causing nausea and other sickly symptoms.2,3 Ethanol (aka more alcohol) stops the body from going after that methanol, saving you from those miserable hangover symptoms.
This means that when an individual consumes alcohol the next day, the body excretes the methanol as is instead of turning it into toxic chemicals.4 So, mediating methanol levels with a dash of ethanol the next day may actually kind of work—until you finally stop drinking, that is.
#2. Endorphin Boost
Drinking alcohol causes a short-term increase in endorphins in the body. These are feel-good chemicals that can mask the unpleasant symptoms of a hangover.
Research shows that alcohol indeed temporarily raises endorphin levels, leading to pleasurable feelings. However, during alcohol withdrawal (hangover), endorphin levels drop.5 Additional drinks, therefore, temporarily distract a person from some of the nastiest symptoms of a hangover.
#3. Blood Alcohol Level
Hangover symptoms develop when the body metabolizes ethanol and blood alcohol levels fall. 6,7 The theory behind the “hair of the dog” hangover remedy is that if you drink more alcohol, your blood alcohol levels will rise and you will no longer experience hangover symptoms. However, when you eventually stop drinking and blood alcohol levels return to zero, the hangover will return.
Bottom line: Does Hair of the Dog Work for Hangovers?
The imaginary science that hair-of-the-dog-ers point to as they grab a morning brew is the idea that drinking alcohol will prevent symptoms of alcohol withdrawal, the thing that causes hangovers. That's part of it, but it's more complicated than that.
Hangovers happen when a high concentration of alcohol in your system sharply drops after you stop drinking. The grim results hit you the hardest when your blood-alcohol level (BAC) reaches zero. Putting a little booze back in your system will temporarily make you feel better, sure. But when your BAC dips down to zilch, you'll be dealing with the symptoms of last night's liquor on top of this morning's bloody Mary.
While the “hair of the dog” hangover cure may have some merit, it also adds more alcohol to your body that will eventually need to be metabolized.
So, while your hangover might be delayed, it will not be prevented entirely.
Bottom line is that the hair of the dog doesn’t actually cure a hangover, but it does temporarily make you feel better.
The NHS advises a more cautious approach to a hangover cure, urging people not to drink on an empty stomach, avoid dark-colored alcohols that have more impurities and down a pint of water before bed.