Nausea, which refers to feeling the urge to vomit, isn’t a medical condition in itself, according to Stanford Medicine. Instead, it’s a symptom of something else, such as an illness or lifestyle change.
“I like to break down nausea into acute and chronic duration,” says Kamal Amer, M.D., a gastroenterologist at Gastroenterology Associates of New Jersey. Acute nausea lasts less than a month and chronic lasts more than a month. Both acute and chronic nausea can be caused by a broad range of factors.
You can usually manage instances of acute nausea yourself, with rest, drinking liquids, or taking over-the-counter medications, he says. For chronic cases, doctors may need to run some tests to check for medical conditions, like GI diseases, diabetes, or a heart condition.
“If you find yourself frequently experiencing nausea that persists, you should get it checked out to get to the root of the problem,” says Christine Lee, M.D., a gastroenterologist at the Cleveland Clinic.
You should also see a doctor if your nausea is accompanied by vomiting blood, an inability to keep any foods or drinks down, high fever, intense pain, and shortness of breath, Dr. Lee says.
Doctors will ask a variety of questions about how intense the nausea is, how often it happens, and how long you’ve been experiencing it to find out what’s causing it, Dr. Amer says.
Even if you never actually vomit, there are several reasons that you might still feel nauseous. Here’s an overview of potential causes and when you should call a doctor.
Why Am I Feeling Nauseous?
There are a number of reasons that you may often feel nauseous, doctors say. The factors can range from mild to serious.
You have a stomach bug or food poisoning.
Foodborne illness or a viral or bacterial infection are common causes of nausea, Dr. Amer says.
If your friends, family members, or other close contacts have had similar symptoms, it likely means you have a stomach bug. You might have food poisoning if you start feeling nauseous after eating something.
Usually, your nausea will resolve in a day or two. If it doesn’t or gets worse, see your doctor.
You started taking a new medication.
Nausea can sometimes be a side effect of non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen, so consult your doctor if this is the case and to see if switching to another painkiller or anti-inflammatory might be a safer bet for you, Dr. Lee says.
You have an alcohol or substance abuse disorder.
Drinking too much alcohol or taking drugs like opioids can irritate the stomach lining, disrupt normal digestion, and cause nausea, Dr. Amer said. Marijuana use can also cause cyclical vomiting and nausea.
“I have begun to see several patients both in the hospital ward setting as well as outpatient setting present with nausea and abdominal distension in association with opiate pain medications,” he says.
Getting help with any alcohol or substance overuse is crucial.
You have low testosterone.
One symptom of low testosterone is frequent feelings of nausea, Dr. Amer says. If you’re also noticing that you have a low libido or struggle to get an erection, it’s a good idea to get your T levels checked.
You have motion sickness.
“If you experience motion sickness where repeated motions such as with riding on a boat or experiencing turbulence on a flight, or even when moving on a rollercoaster or a car ride, you should still talk to your doctor,” Dr. Lee says.
If you’re otherwise fine and experiencing common motion sickness, “you might find ensuring you’re well-hydrated can help you get to the root of the problem and possibly avoid it in the future,” she says.
You’re just really hungry.
It may seem counterintuitive, but it’s common that being hungry might make you feel like you want to throw up. The reason is that the buildup of stomach acid when you’re extremely hungry may make you feel sick, Dr. Lee says.
This one’s pretty easy to remedy: Don’t skip mealtimes, and find a snack if you start feeling hungry. Also, make sure you properly fuel up for a workout—exercising on an empty stomach may make you nauseous, dizzy, or lightheaded.
You have anxiety.
Stress, fear, nerves, and anxiety can give you butterflies in your stomach or even nausea, Dr. Lee says.
It’s easier said than done sometimes, but learning to control stress can help. If your anxiety levels seem to be interfering with your day-to-day, it’s probably a good idea to talk to a therapist or counselor who you feel might help.
You have cyclic vomiting syndrome.
This condition, also known as CVS, can cause sudden, repeated bouts of severe nausea and vomiting, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Episodes can come and go and last from a few hours to several days.
Experts aren’t sure what causes CVS, but doctors often perform tests to rule out other conditions before diagnosing it. Treatment may include medication or avoiding triggers, such as certain foods.
You’ve had anesthesia or chemotherapy.
If you’ve just had surgery and are loaded up on pain medications or narcotics, or you’ve been receiving chemotherapy, nausea is a common side effect, Dr. Lee says. Before any of these procedures, talk to your medical team about what to expect.
“Nausea and vomiting are very common when you wake up after having received anesthesia, so your provider should ask if you have this history and provide you with anti-nausea medications beforehand, if necessary,” she says.
You have a balance disorder.
Balance disorders such as vertigo, labyrinthitis, and vestibular neuronitis are commonly accompanied by nausea, Dr. Lee says. In this case, getting to the root of the problem can help you manage your nausea.
You’ve been sick recently.
You may experience feelings of nausea after a cold or other upper respiratory tract infection, such as Covid-19, Dr. Amer says. The nausea will likely go away once you feel better, but see your doctor if it persists.
You have a GI disorder.
There’s no surprise that nausea can be tied to a digestive or gastrointestinal disorder, such as gastroparesis, gastritis, PUD (peptic ulcer disease), GERD (gastroesophageal reflux disease), inflammatory diseases, pancreatic disorders (such as pancreatitis or gallstones), intestinal obstruction (such as constipation, bowel obstruction or appendicitis), Dr. Lee says.
You have another underlying medical condition.
Other serious causes can be vascular disorders such as heart artery blockages, blood clots, or a brain-related issue such as meningitis or a hemorrhage.
Finally, hyper- or hypoglycemia (too high or too low blood sugar), dehydration, and heat stroke can also be contributing causes of nausea. Dr. Amer said people with “poorly controlled diabetes” often have issues emptying their stomachs and may experience nausea.
Liver or kidney issues may also cause nausea, he added.
If you are really always nauseous, meaning it’s frequent and recurring, you want to see a doctor to rule out these serious conditions.
When to See a Doctor
Because the range of reasons you feel nauseous all the time is so vast, it’s important to focus not just on the symptoms, but to know all of the possibilities. If nausea seems to come out of nowhere and sticks around, see your doctor.
“I usually tell my patients to call me if symptoms persist for several hours,” Dr. Amer says.
Call your doctor if you have nausea along with other symptoms such as abdominal pain, fever, sweating, increased work of breathing, chest pain, shortness of breath, bloody vomit or stool, weight loss, changes in skin or eye color, and recurrent vomiting, diarrhea, or constipation, he says.
“The earlier the diagnosis, the better the prognosis and outcome, so the message we want to send is to seek medical attention to make sure it’s not anything serious,” Dr. Lee says.
Emilia Benton is a Houston-based freelance writer and editor. In addition to Runner’s World, she has contributed health, fitness and wellness content to Women’s Health, SELF, Prevention, Healthline, and the Houston Chronicle, among other publications. She is also an 11-time marathoner, a USATF Level 1-certified running coach, and an avid traveler.
Erica Sweeney is a writer who mostly covers health, wellness and careers. She has written for The New York Times, HuffPost, Teen Vogue, Parade, Money, Business Insider and many more.