New York, Dec. 28: Little can suck the joy out of the holiday season like losing a day or two to nurse THE WORST HANGOVER IN THE HISTORY OF THE WORLD.

Other than suffering a blinding migraine while riding a puke-inducing ride, nothing can compare to the agony that follows after having one — or five — too many drinks.

But what the heck exactly is a hangover, how does one prevent it (short of sticking to juice and soda)? Is there a way to “cure” a hangover once the pain (oh, the pain) has started? Please note: These questions aren’t asked in an effort to encourage binge drinking. If that’s the behaviour you’re engaging in on a regular basis hangovers are the least of your problems. Get some help, pronto. For the rest — well, we all have our own versions of remedies.

But is there any hope of curing or avoiding a hangover?

Joseph P. Reoux, who works at the Seattle VA Puget Sound Health Care System’s addictions treatment centre, says that on the most basic level, a hangover is caused by toxins. “Hangover is the body’s reaction to excessive levels of alcohol the night before. Even after the alcohol isn’t present in the bloodstream the next day, your body still feels the effects.”

Those effects are toxic, primarily in two ways.

The first, says Reoux, are the direct effects of the alcohol, specifically congeners, the byproduct of alcohol production (fermentation and distillation). Congeners wreak havoc on the body in a number of ways, primarily by causing nasty headaches. There are more congeners present in dark alcohols (whisky, brandy and wines in general) than in lighter drinks (gin and vodka).

Then there’s acetaldehyde — a byproduct of alcohol metabolism that causes severe headaches, nausea, and vomiting as well as flushing or burning of the skin when present in excess. So it’s reasonable to think that this metabolite of alcohol may be involved in hangovers.

Eating a little something or taking an antacid might help things, but they’re not magic bullets. For starters, they won’t prevent the dehydration alcohol causes. “When the body is dehydrated, it experiences dry mouth, fatigue and headaches,” says Reoux. The chemical imbalances caused by excess alcohol then contribute to the flu-like symptoms the hungover tend to experience (everything from body aches to diarrhoea).

Jamey Wallace, medical director at the Bastyr Centre for Natural Health, says alcohol metabolism is a double-edged sword for the body.

“Alcohol depletes the body of water, and you need water to metabolise it, so it’s a double whammy,” says Wallace. “Before people go out, they ought to have two glasses of water.” He also advises that each alcoholic drink be preceded by a glass of water.

Another substance that can bring on the morning-after pain is lactic acid (a substance your body produces during heavy exercise, causing soreness).

When faced with alcohol, the body’s number one priority is to process it. This, says Reoux, “allows other waste products to build up. One of these is lactic acid. Too much lactic acid can result in muscle aches and fatigue.”

Additionally, he says, excess alcohol can trigger cardiac-related deaths via irregular heartbeats, known as “holiday heart syndrome”.

Another reason drinkers feel like butt after a big night is that alcohol disrupts normal sleep patterns, reducing the amount of restorative sleep for the drinker. This compounds the agony felt by a dehydrated body, sore muscles and a sick belly.

Alcohol also is known as a central nervous system depressant — a downer, not an upper. The slurring, the sloppiness, the clumsy movements and slow-witted banter are evidence of this when one is drunk, but Reoux says the depressant effects of alcohol are present and accounted for during the hangover phase as well.

“One of the things that people may not recognise as easily as the physical symptoms is that the next day they are slower to process information and their manual dexterity — their visual spatial skills — are impaired.” This, says Reoux, puts people at greater risks for accidents.

Just to be clear: Reoux says there’s no chemical that can reverse alcohol intoxication.

Your best bet (assuming moderation is out the window) is to keep hydrated, keep some food in your stomach, and take a couple of aspirin or ibuprofen in the morning. Reoux says non-steroidal anti-inflammatories can help with the thumping headache but can be hard on the stomach (especially for those prone to stomach bleeding), so check with your physician. And whatever you do, don’t try to save calories by drinking on an empty stomach.