The medical term for a hangover is veisalgia, and it's absolutely perfect—so on the nose it's hard to believe it's real. The word's roots are Norwegian and Greek; "uneasiness following debauchery" (kveis) and "pain" (algia). I mean…
We've certainly all been there, buried in a debt of pain when the bill from the previous night's partying comes due—the joy and fun and bliss of the night disappearing with the morning sun, replaced with a brain-splitting, body-flattened regret that leaves you bargaining with God. Just one symptom of the common hangover—headache, sensitivity to light and sound, fatigue, nausea—could ruin your day. Combine them, and you want to die. Fortunately, (unfortunately?) you won't.
There is no cure (save for time, which we'll get to later). Once you're in the throes of a hangover, you can only seek to understand why your body is making you pay such a brutal price. To do just that, we talked to Jerrold B. Leikin M.D., Director of Medical Toxicology at NorthShore University HealthSystem. He explained the physiology of a soul-crushing hangover to us in painstaking detail. Here's what's going on inside that temple of yours.
Hangovers are basically mini alcohol withdrawals. As you drink, alcohol affects the neurotransmitters for chemicals in your brain, says Leikin. Initially, drinking makes you feel euphoric because the disruption of these neurotransmitters results in large amounts of reward chemicals, like dopamine, being released all at once. Your brain adapts to these changes, and when the alcohol is removed, the opposite reaction occurs. In essence, you go from feeling like The Shit, to just plain feeling like shit. Why?
"As it's being metabolized, alcohol is oxidized into a substance called acetaldehyde, which makes you feel awful," says Leikin. "Acetaldehyde is a really toxic metabolite. It's more toxic than alcohol itself in a lot of ways. If you get too much of it, you'll feel dysphoric, you'll start to feel nauseous, your head will start to hurt, and it can exacerbate depression."
If you'd kept the drinking to a minimum, your liver would have been able to get rid of the acetaldehyde before it had time to do much damage. But you didn't, so your liver's store of glutathione–a chemical that would normally attack acetaldehyde and break it down into a less harmful substance–has been severely depleted by the amount of alcohol you sucked into your poor, broken body. Hence, everything hurts.
Headache, Fatigue, and Sensitivity
The reason even small movements send throbs of agony rocketing through your temples? According to Leikin, it's because "alcohol intoxication causes what's known as vasodilatation, or expansion of the blood vessels." Vasodilation has been touted as a cause of migraines, so from the get-go, it's not good. As the effects of alcohol start to wear off, the blood vessels in your head begin to retract in a process called vasoconstriction, which further causes headaches. "Any time blood vessels expand or contract, there is going to be pain," said Leikin. "It can be expected that alcohol hangovers can exacerbate migraines for this reason."
What's more, says Leikin, the disruption of those neurotransmitters we talked about earlier are why you have an extreme sensitivity to light and sound when hungover. Excess alcohol disrupts your body's biological rhythms, which messes with your sleep cycle, the reason you feel so tired.
Dehydration Station: Population, You
Alcohol...makes you pee. Have you heard this? Experienced it, even? Well, all that tinkling takes a toll on your body. Alcohol ("technically it's a diuretic, says Leikin) essentially tricks your kidneys into peeing out significantly more liquid than you put in by blocking a hormone called antidiuretic hormone (which Leikin refers to as ADH), that usually aids the process of water absorption.
"Drinking just 50 grams of alcohol can cause the elimination of, eventually, up to a quart of water over several hours," says Leikin. This is what causes your many drunken trips to the bathroom while out on the town. But pissing the night away isn't the only reason you feel like a dried-out sponge. "Don't forget, sweating is a common hangover symptom," says Leikin.
Your Stomach and Asshole
"The nausea you feel during a hangover is due to the fact that alcohol is an irritant to the stomach," says Leikin. "It causes gastritis, or inflammation of the stomach lining."
According to Leikin, alcohol causes a buildup of lactic acid in the body, as well as increased pancreas and intestinal secretion. "Alcohol stimulates the pancreatic enzymes, which makes the pancreas secrete more than usual," he says. "Any one of these things can cause nausea, vomiting and diarrhea." All together, they conspire to keep you within arm's reach of a toilet for a good portion of your day.
A Thick Fog Blankets Your Brain
There are many reasons why you just can't concentrate while hungover, says Leikin, and if you've read this far you can probably figure it out on your own. "You're dehydrated and your electrolytes are likely at abnormally low levels." You have a lot of acetaldehyde building up in your system, and you're also dealing with all the intestinal disturbances we just talked about. In addition to that, your blood sugar may be low or wacky overall." Also, remember, you likely didn't sleep very well. Any one of these things on their own would cause concentration problems, he says. "Combined, it's going to be difficult for you to get anything done."
Off to the Races: Your Heart
"Alcohol has a direct effect on the heart," says Leikin. "There's actually a condition we call Holiday Heart, which is arrhythmia [irregular heartbeats] that is caused by alcohol abuse."
Holiday Heart, or atrial fibrillation, happens for a variety of reasons: alcohol can weaken the heart muscle, which can lead to irregular beats. It also messes with the way your heart responds to adrenaline, and depletes your store of electrolytes like magnesium, sodium, and potassium, which can in turn affect the heart's electrical currents.
You're All Up in Your Feelings
If you're feeling extra weepy during a hangover, you're not alone. An endorphin crash is to blame, which leaves you emotionally vulnerable and a bit down in the dumps. It's the reason, say, you started crying hysterically when your favorite contestant on The Great British Bake Off pulled a soggy bottom and got sent home. "This is what we call emotional lability, which is characterized by overreactions to small triggers," says Leikin. "Think about it: the dehydration alone makes you dizzy and lightheaded, and that contributes to your emotional state."
Nothing You Can Do About It
There are countless hangover cures on the market, and a (no pun intended) thirsty public hoping like hell they work. Surely, something exists that makes the pain go away, right? Right? "There is no cure for a hangover," says Leikin. "It's pretty much down to symptomatic treatment and time. Basically it takes time for your electrolytes to become normalized and recover. Drinking something like Pedialyte might make sense as a symptomatic cure, but I can't endorse any of that. Only time cures hangovers."
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