Woke Up Feeling Hungover but Didn't Drink? Here's What Your Body's Trying to Tell You

True hangovers happen from drinking too much alcohol (and yes, they do get worse with age). But there are a lot of other things that can make you ​feel​ like you're recovering from a night of heavy drinking even if you didn't consume any booze at all.

Symptoms like dehydration, nausea or vomiting, headache, dizziness and fatigue, after all, are all classic signs of a hangover. But they're also common symptoms associated with a number of other problems. Here's how to figure out what might be ailing you, and what you can do to feel better fast.

Dehydration is actually one of the major culprits of an actual hangover, says Donna Casey, MD, an internist at Texas Health Presbyterian Hospital Dallas. So it's not surprising that simply not having enough fluids can leave you feeling lousy. Even losing just 1.5 percent of your body's fluids can leave you with a headache, fatigue, dry mouth and dizziness, notes the Cleveland Clinic.

Falling short on fluids, too, can lead to fluctuations in levels of the body's electrolytes like sodium and potassium. And those imbalances can also cause hangover-like symptoms, Dr. Casey points out. Think muscle aches, lightheadedness, heart palpitations and weakness.

​Fix it:​ Start rehydrating by taking small, frequent sips of water, broth or an electrolyte-rich drink like Pedialyte or Gatorade, Dr. Casey recommends. Resist the urge to chug. "Doing so will actually cause the body to excrete more fluid and perpetuate the problem," she says.

A nasty bug can definitely mimic symptoms of a hangover. "Much of this overlap is related to dehydration and electrolyte abnormalities," Dr. Casey says.

Too much booze can also irritate the lining of your GI tract and cause symptoms similar to a stomach bug like nausea or vomiting, as well as sweating, a fast heart rate and skin flushing, she notes.

​Fix it:​ Resting as much as possible and drinking plenty of fluids are the best ways to treat flu-like infections, according to the Mayo Clinic. An over-the-counter pain reliever like acetaminophen or ibuprofen can help if you're achy or feverish, too.

Going big on the sweet stuff at night can potentially leave you feeling crummy the next day. "Excessive sugar before bed can cause spikes and crashes in blood sugar to occur, which can lead to disruptive sleep and headaches as well as feelings of shakiness, nausea or general fatigue," explains registered dietitian and certified diabetes educator Erin Palinski-Wade, RD, CDE.

Keep in mind that "excessive" means different things to different people. "We each respond to food and sugar in our own way. For some, it may take a large amount of added sugar to impact how we feel the next day," Palinski-Wade says. "For a person with insulin resistance or diabetes, just small amounts of added sugar can cause these feelings."

​Fix it:​ You can combat the effects of low blood sugar by drinking plenty of water and eating a balanced breakfast with lean protein, healthy fat and complex carbohydrates. "Try scrambled eggs with mashed avocado on a slice of whole-grain toast," Palinski-Wade recommends. Some easy exercise like walking helps too.

Whether you're trying to quit coffee or just didn't have time to get to your morning cuppa, skipping caffeine when your body expects it is a recipe for feeling, well, awful.

"Symptoms related to caffeine withdrawal include primarily headache, but it may manifest with drowsiness or sluggishness, brain fog, irritability, difficulty concentrating, decreased alertness and depressed mood," Dr. Casey says. "And at the extreme end, it can include nausea, vomiting and muscle aches."

​Fix it:​ If you're cutting out caffeine on purpose, you'll minimize symptoms of withdrawal by dropping your consumption gradually, Dr. Casey says. Try trimming back by just a few ounces each day instead of going from a full cup of coffee to nothing at all. And if you just didn't get around to having coffee at your usual time, go make a cup ASAP.

Sleeping pills or antidepressants with a sedative effect might help you log more shut-eye, but they can often leave you feeling dizzy, nauseous or headache-y in the morning. In fact, 8 out of 10 people actually say they feel like they have a hangover the day after taking a sleeping pill, according to the Cleveland Clinic.

​Fix it:​ Talk with your doctor if your sleeping medication is causing hangover-like side effects the next morning. It may be possible to adjust your dose or try a different drug.

Alcohol is a common migraine trigger. But even without drinking, waking up with a migraine can feel a lot like the morning after a night of heavy boozing.

In addition to the throbbing head pain, migraines can leave you feeling nauseous and sensitive to light, notes the National Institutes of Health (NIH). Even after the pain subsides, you might feel weak or exhausted.

​Fix it:​ There's no cure for migraine, but you may be able to lessen the intensity by taking action against your symptoms as soon as you notice them. Taking your prescribed migraine medication, moving to a dark and quiet room, drinking fluids and placing a cool cloth on your forehead can help, per the NIH.

Alcohol and pregnancy don't mix, of course. But morning sickness can cause queasiness or vomiting (at any time of the day), and early pregnancy in general can make you feel tired and worn out. It's normal to have aversions to certain foods or smells, too, per the Mayo Clinic.

​Fix it:​ For nausea relief, try sucking on ice chips or popsicles to stay hydrated and stick with small, frequent meals instead of bigger ones, recommends ob-gyn Felice Gersh, MD, founder and director of the Integrative Medical Group of Irvine in Irvine, California.

You can also ask your practitioner about taking 50 milligrams or less of vitamin B6 daily, which may help ease symptoms of morning sickness, she says.

Sometimes hangover-like symptoms have a relatively benign cause and a simple fix, like being mildly dehydrated or having a sugar feast before bed. But other times they could be a sign that something is wrong, especially if you wake up feeling hungover without drinking more than once.

If you can't pinpoint an obvious cause for why you're feeling so lousy or can't ease your symptoms with simple at-home measures (like drinking more water or resting), call your doctor, Dr. Casey recommends. "The symptoms could be indicative of another severe illness or severe dehydration that requires immediate medical attention," she says.