Why Do I Feel Nauseous? 11 Common Causes & What to Do

Updated in March 2023

Feeling nauseous does not necessarily mean it will lead to vomiting. You can feel nauseous as a result of eating fatty foods, gastritis or being pregnant. Some people may feel the urge to vomit on a bumpy car or boat ride, or if they see something gross or repulsive. 

The urge to vomit usually comes before vomiting and is associated with symptoms like general malaise, a bitter taste in the mouth and cold sweats.

 Feeling nauseous usually resolves within a few hours. However, if it persists for over a day, is very uncomfortable or occurs for no apparent reason, you should see a doctor for assessment. 

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The urge to vomit can occur for the following reasons: 

1. Diet changes

Over-eating or eating many fatty foods can make digestion more difficult, leading to nausea and, many times, vomiting. 

In addition, food poisoning or an intolerance to a type of good can cause gastrointestinal symptoms like diarrhea, general malaise, nausea and vomiting. 

2. Labyrinthitis 

Labyrinthitis is an inflammation of an inner ear structure called the labyrinth. Swelling in this area is associated with vertigo, which is often accompanied by nausea. 

3. Gastrointestinal problems 

Some gastrointestinal issues, like gastritis, gastroenteritis, GERD and pancreatitis can cause, among other symptoms, general malaise, heartburn and the urge to vomit. Nausea normally appears after meals and can be very uncomfortable. 

4. Digestive hemorrhage 

A digestive hemorrhage is associated with bleeding anywhere along the digestive tract. It can cause nausea and dark vomiting, and can occur with conditions like Mallory-Weiss Syndrome, neoplasias, ulcers from stress and hiatal hernias

5. Migraine

A migraine is described as a an intense, throbbing pain on one side of the head. It can cause symptoms like nausea, and vomiting if the pain is very intense. It is important to consult a doctor or neurologist to identify the cause of the migraine and initiate treatment is appropriate. Read more about the symptoms of a migraine and what to do.

6. Hangover

A hangover occurs after excessive alcohol intake, and is is characterized by general malaise, headache, eye pain and nausea. These symptoms are usually a result of an overloaded liver working to eliminate the alcohol, as well as dehydration that ensues from over drinking. Check out our tips on how to cure a hangover at home.

7. Infections

Viral, fungal, bacterial or protozoan infections can cause various symptoms that emerge when the microorganism reaches the gastrointestinal system. An infection can cause nausea and vomiting. Therefore, if you suspect you may have an infection, you should see a doctor for assessment and treatment to prevent worsening. 

8. Psychological disorders

Some psychological issues, like stress and anxiety, can cause mental symptoms as well as physical symptoms like nausea, stomachaches, increased heart rate or difficulty breathing. 

9. Intense physical activity 

Exercising intensely, especially if you are not conditioned to do so, can prompt an urge to vomit. This is because exercising leads to changes in blood circulation, and depending on the intensity of activity, this can cause increased lactic acid production by the muscles, which can accumulate in the blood. Vomiting is the body’s natural mechanism to eliminate this excess lactic acid. 

10. Pregnancy

Nausea is one of the main symptoms of pregnancy and it normally occurs after the sixth week of gestation. The urge to vomit is one of the first symptoms felt my pregnant, with many reporting more nausea in the morning. The urge to vomit in pregnancy does not always lead to vomiting, although it should be reported to a gynecologist if it occurs frequently. See other early pregnancy symptoms that can occur in the first weeks. 

Nausea and the urge to vomit that occurs constantly in pregnancy is referred to hyperemesis gravidarum. If severe, it may require IV treatment and nutrition in a hospital setting to prevent complications in the mother and baby. 

11. Hypoglycemia

Hypoglycemia is defined as a reduction in blood glucose levels. It leads to symptoms like dizziness, vertigo, lack of coordination and nausea. One of the main causes of hypoglycemia is excess insulin in the body.

What to do

If you feel the urge to vomit, you can take over-the-counter nausea medication, like Bismuth subsalicylate or dimenhydrinate. These should be taken as instructed by a pharmacist or doctor. 

In addition to medications, you should avoid eating very heavy or fatty meals, as they are harder to digest and cause more nausea. Plenty of water is also advised (with lemon juice added if preferred). There are also teas that can help to calm gastrointestinal symptoms, like peppermint tea or ginger tea. Learn more about teas for nausea that you can make at home.