The alarm blares like a four alarm fire; you crack open your eyes only to be blinded by the glare of daylight. With a throat so dry you can barely swallow, you stagger to the bathroom and gulp down a glass of water…only to be slammed with a wave of nausea that makes the room spin as you hurl the water back up.

Yes, it's obvious you have a hangover, but what exactly is it and why is it attacking you?

Simply put, a hangover is caused by overindulgence in alcohol. The symptoms aren't the same for everyone, and the causes are more complex than just having a few too many drinks.

Definition of a Hangover?

A hangover is a group of symptoms that may develop after too much alcohol consumption. Although the general rule of thumb is, the more you drink the worse your hangover will be, there's a wide range of effects from person to person.

You may only have a headache, or you may have any combination of the following symptoms:

  • Rapid heartbeat
  • Fatigue and weakness
  • Headaches and muscle aches
  • Excessive thirst and dry mouth
  • Increased sensitivity to light and sound
  • Nausea, vomiting, or stomach pain
  • Shakiness
  • Dizziness or a sense of the room spinning
  • Poor or decreased sleep
  • Decreased ability to concentrate
  • Mood disturbances such as depression, anxiety, and irritability

Because a hangover can last up to 24 hours it may affect your workday. In addition, although your blood alcohol level has dropped to zero you may have impaired reaction times if your symptoms are severe, possibly making you prone to accidents.

Although the quantity of alcohol consumed is the usual key to developing a hangover, other factors may affect different people. How fast you drink or mixing types of alcohol may give you a hangover, or you may be one of the few people who never notices adverse symptoms the morning after you overindulge.

Hangover Causes

Why does drinking too much alcohol give you a hangover? For the most part it's because alcohol speeds up dehydration, but there's a group of other chemical reactions which also create adverse reactions:

  • Alcohol triggers your immune system, which decreases your appetite and can cause memory problems and an inability to concentrate.
  • Imbibing causes you to urinate more frequently, speeding up dehydration and leaving you lightheaded, dizzy, and thirsty.
  • Drinking can lower your blood sugar and cause weakness, shakiness, and fatigue.
  • Alcohol can irritate the lining of your stomach and increase stomach acid, causing nausea, vomiting, and abdominal pain.
  • Drinking causes your blood vessels to expand, which may give you a headache.
  • Alcohol can disrupt your deep sleep cycle, so even though it may make you sleepy you’ll still wake up tired and groggy.

Factors That Affect Your Hangover

Although the only way to guarantee you won't get a hangover is to abstain from alcohol, there are a number of factors you can use to your advantage to lessen or prevent the occurrence.

Here's a look at the most common:

  • Eat before you indulge. This will slow the absorption of alcohol and protect the lining of your stomach.
  • Avoid tobacco and other drugs, as they can compound the symptoms of a hangover.
  • Be choosy about your drinks. Darker colored alcohols such as bourbon and brandy contain more congeners, which can make your symptoms worse.
  • Stay hydrated. Drink plenty of water or juice in between alcoholic beverages.
  • Act your age. The older you are, the more effect alcohol may have on your system.
  • Know your genetics. If you have a family history of alcohol abuse you may be more prone to hangovers.
  • Genders aren't equal when it comes to alcohol. Because women are smaller than men, they will not only become inebriated sooner, they are also more prone to have hangovers afterward.
  • Know yourself. Some people can drink like a fish and never have a hangover, while others can feel like they're at death's door after only one drink.

Other Hangover Symptoms You May Not Notice

You may think your hangover is under control and you're doing great, but there are some symptoms you may not even realize you have. The most common are trouble concentrating, lack of dexterity, and memory problems. A hangover may affect your performance at work or school because you're missing days, are constantly late, or even falling asleep on the job. You're also more prone to injuries in the workplace and conflicts with family or coworkers; you may find yourself having trouble completing your usual tasks. And, chances are, even if you think you're doing a great job masking your misery, those around you are quite aware you're not functioning at 100%.

When Does a Hangover Become a Problem?

There's a fine line between having an occasional fun night out and having a drinking problem. If your alcohol consumption is interfering with your job or personal life, there's a strong chance you are sliding into abuse.

The National Institute on Alcohol Abuse and Alcoholism (NIAAA) states some of the common problem signs of alcohol use disorder are:

  • Drinking secretly or alone
  • Blacking out and missing blocks of time
  • Not being able to stop after one or two drinks
  • Losing interest in hobbies
  • Feeling irritable when the usual drinking hour approaches and you can't indulge
  • Having an urge to drink
  • Gulping drinks to become buzzed
  • Having problems with the law, relationships, work, or school because of your drinking
  • Hiding alcohol in odd places
  • Needing more and more alcohol to feel the effects
  • Experiencing shaking, sweating, or nausea when you can't have a drink

Keep in mind, people don't become alcoholics overnight. The NIAAA reports it takes an average 10 years to become alcohol dependent, so just because you don't have all the above signs doesn't mean you don't have a problem. Even if you only have a few of the signs, it's probably time to seek help to lower your habitual alcohol consumption.

How Long Does a Hangover Last?

Almost all hangovers are gone in 24 hours, but they can last up to 72 hours. Generally speaking, the factors listed above will determine how long a hangover lasts. So, if you have a meal, drink moderately, and stay hydrated you have better chances of a short hangover the next day.

In the worst case scenario, a hangover can mask alcohol poisoning. If you or someone you're with experiences irregular or slowed breathing, a drop in body temperature, pale or bluish skin, vomiting that won't stop, or seizures; you should seek medical help immediately. Alcohol poisoning can be deadly and should be considered a medical emergency.

Curing Your Hangover

Alas, there is no magic cure for hangovers and the only sure prevention is abstinence or to drink in moderation. It appears everyone knows that one person who swears by "the hair of the dog" but they are wrong and a drink the next day will only make things worse.

Here's the best way to treat a hangover:

  • Hydrate. Drink plenty of water or juice throughout the day; sports drinks with added electrolytes can also help you regain the hydration you lost.
  • Eat something. Bouillon, soup, toast, or similar bland foods will boost your blood sugar and replace lost salt and nutrients.
  • Take a pain reliever, but not acetaminophen (Tylenol) because it can quickly damage your liver. Make sure you eat something first, even if it's just a couple of crackers, so the pain reliever doesn't irritate your stomach.
  • Get more sleep. Because the hangover isn't going to go away any faster, you might as well sleep and let your body rejuvenate. If you're lucky, when you wake up all the symptoms will be gone.

Hangover Prevention

While abstinence is the only guarantee to preventing a hangover there are key tips you can follow to make it less likely to occur after a night on the town. Knowing your personal limit is the biggest: if you can only handle one drink, then so be it. Don't let other drinkers push you into drinking more than you know you can handle.

  • Eat. Have a meal before you drink and snack while you're enjoying your drinks. This will slow the absorption of alcohol and protect the lining of your stomach.
  • Remember congeners. Choose lighter colored beverages such as vodka and light colored ales.
  • Hydrate. Sip water in between sips of alcohol and you'll be less likely to dehydrate.
  • Keep it slow. Make each drink last about an hour, or alternate alcohol with water to make the one hour mark.
  • Avoid tobacco and other drugs. Even secondhand smoke can affect you, so keep the ashtrays at a distance.
  • Skip the "miracle cures." That pill at the gas station that says it will prevent a hangover will do no such thing.