Nausea
A diffuse sensation of unease and urge to vomit.
Nausea is a broad, unsettling feeling of discomfort, often described as a need to vomit. When it lasts for a long time, it can become severely disabling, with people reporting a sense of unease in the chest, stomach, or the back of the throat. A 2011 book on the subject cataloged more than 30 different attempts to define the sensation.
Because nausea is a non-specific symptom, it can stem from a wide variety of causes. The most common triggers include gastrointestinal infections and other digestive disorders, food poisoning, motion sickness, dizziness, migraines, fainting, low blood sugar, anxiety, overheating, dehydration, and lack of sleep. Many medications, such as chemotherapy drugs, list nausea as a side effect, and it is also a hallmark of early pregnancy, known as morning sickness. Disgust and depression can also bring it on. Drugs used to prevent or treat nausea and vomiting are called antiemetics; in the United States, the most frequently prescribed are promethazine, metoclopramide, and the newer ondansetron. The word itself comes from the Latin *nausea*, which traces back to the Greek *nausia* (or *nautia*), meaning seasickness, and is rooted in the word for a ship.
**Causes**
Gastrointestinal infections account for 37% of acute nausea and vomiting cases, with food poisoning being the second most common cause. Side effects from medications (3%) and pregnancy are also frequent. Chronic nausea has many possible origins, and in about 10% of cases, the cause remains unknown. Aside from morning sickness, there are no sex-based differences in how often people report nausea. After childhood, the rate of doctor visits for nausea steadily declines with age; among people over 65, less than one percent of medical appointments are for this symptom.
**Gastrointestinal** Acute nausea and vomiting most often come from a gastrointestinal infection. Chronic nausea can be the main symptom of many digestive disorders, including gastroesophageal reflux disease, functional dyspepsia, gastritis, biliary reflux, gastroparesis, peptic ulcer, celiac disease, non-celiac gluten sensitivity, Crohn's disease, hepatitis, upper gastrointestinal malignancy, and pancreatic cancer. An uncomplicated *Helicobacter pylori* infection does not cause chronic nausea.
**Food poisoning** Food poisoning typically triggers a sudden onset of nausea and vomiting within one to six hours of
- common causes
- Gastroenteritis, food poisoning, motion sickness, migraine, anxiety, pregnancy
- most common acute cause
- Gastrointestinal infections (37%)
- medication class
- Antiemetics
- commonly prescribed antiemetics in US
- Promethazine, metoclopramide, ondansetron
- etymology
- From Latin nausea, from Greek ναυσία – nausia, 'seasickness'
Lore & Background
Nausea is a non-specific symptom with many possible causes, including gastrointestinal disorders, food poisoning, motion sickness, dizziness, migraine, fainting, low blood sugar, anxiety, hyperthermia, dehydration, and lack of sleep. It is also a side effect of many medications, including chemotherapy, and occurs as morning sickness in early pregnancy. Nausea may also be caused by disgust and depression. Gastrointestinal infections (37%) and food poisoning are the two most common causes of acute nausea and vomiting. Side effects from medications (3%) and pregnancy are also relatively frequent. Chronic nausea may be the presentation of many gastrointestinal disorders, such as gastroesophageal reflux disease, functional dyspepsia, gastritis, biliary reflux, gastroparesis, peptic ulcer, celiac disease, non-celiac gluten sensitivity, Crohn's disease, hepatitis, upper gastrointestinal malignancy, and pancreatic cancer. Uncomplicated Helicobacter pylori infection does not cause chronic nausea.
Reader's Guide
Nausea is a common and often debilitating symptom with a wide range of causes, from benign conditions like motion sickness to serious disorders such as pancreatitis, heart attack, or meningitis. Its pathophysiology involves four general pathways: the central nervous system, the chemoreceptor trigger zone, the vestibular system, and peripheral pathways. Medications taken to prevent and treat nausea and vomiting are called antiemetics, with promethazine, metoclopramide, and ondansetron being the most commonly prescribed in the US. While most causes are not serious, nausea can signal life-threatening conditions, and in about 10% of cases, the cause remains undiagnosed. The symptom is particularly common in early pregnancy, affecting nearly 80% of women in the first trimester. Understanding the underlying cause is crucial for effective treatment.
Did You Know?
- Over 30 definitions of nausea were proposed in a 2011 book on the topic.
- Gastrointestinal infections cause 37% of acute nausea and vomiting cases.
- The word nausea comes from Greek ναυσία, meaning 'seasickness'.
- Nausea and vomiting remain undiagnosed in 10% of cases.
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