Nausea is the unpleasant sensation of needing to vomit. Increased saliva in the mouth can occur with nausea. Vomiting is the forceful movement of stomach contents out through the mouth. Muscles in the abdominal wall squeeze tightly to increase pressure inside the abdomen necessary for vomiting. Retching results from abrupt increase in abdominal pressure without vomiting, also called ‘dry heaving’, which can precede or follow vomiting. Similarly, nausea can occur without vomiting or may precede vomiting.
Regurgitation is the effortless movement of swallowed food contents or stomach acid from the stomach back into the mouth. Regurgitation is not associated with nausea or retching. When sour and bitter, regurgitation may be a manifestation of reflux disease, but when it tastes the same as ingested food, it indicates a problem with food movement from the swallowing tube into the stomach. Rumination consists of regurgitation of ingested food followed by rechewing and reswallowing, and is a learned behavior that may be considered pleasurable by the patient. Both regurgitation and rumination need to be differentiated from vomiting by taking a good history.
Nausea and vomiting are distressing symptoms that can make it difficult to go to work or perform normal activities. Nausea and vomiting after surgery, associated with pregnancy and acute infectious illnesses can cause absence from work and medical expenses. In the United States, it is estimated that the cost of acute stomach infections causing nausea and vomiting exceeds $1 billion dollars per year in medical expenses alone; the cost of absence from work and lost productivity may be even higher. Some patients feel that nausea and vomiting after surgery is worse than pain after surgery. Nausea and vomiting following a surgical procedure can result in longer hospital stays and higher costs of hospitalization. As many as 8 out of 10 pregnant women develop nausea and vomiting in the early stages of their pregnancy, resulting in time away from work or home. Nausea and vomiting due to cancer chemotherapy can reduce ability to complete household tasks, enjoy meals, spend time with others and perform day-to-day activities.
Common causes of nausea and vomiting include the following:
Nausea is often described as a “queasy sensation" or a feeling of being “sick to the stomach.” Nausea may occur with or without vomiting and vomiting can occur without nausea. These symptoms may be accompanied by a sensation of flushing, sweating, salivation, lightheadedness and upper abdominal discomfort. Important associated symptoms include: a decreased interest in eating (anorexia), a fear of eating due to unpleasant symptoms (sitophobia), and feeling full early after eating only a small amount of food (early satiety). Associated symptoms and illnesses prior to the onset of nausea and vomiting can help your doctor determine the cause. The cause of acute nausea and vomiting can very often be diagnosed by doctors just by listening to the patient’s history and performing a physical examination. However, chronic nausea and vomiting, when symptoms have lasted longer than 1 month, is more challenging to diagnose and treat.
The cause of an acute episode of nausea and vomiting is often diagnosed by the doctor asking questions and examining you. Tests are only performed if the cause is unclear, or to find out if there are harmful results from nausea and vomiting. If nausea and vomiting are due to a minor illness or short-term problem, there may be no reason to worry, and simple medicines may help. However, your doctor will decide if hospital admission or tests are needed, or if simple medicines are needed. Hospital admission may be needed for very old and very young persons, as they can become dehydrated quickly. If diarrhea or dehydration are present, intravenous fluids may be needed, so it may be better so see a doctor in the office or emergency room, to decide if hospital admission is needed. Finally, even if symptoms are not particularly severe, hospital admission may be needed for tests and further treatment if symptoms do not improve after several days.
First step: identify and treat harmful results of nausea and vomiting, such as dehydration or alteration in chemical levels in the blood (electrolyte imbalance).
Second step: determine the cause of nausea and vomiting, and treat this if found.
Third step: If no cause is found, treat symptoms.
Dehydration (reduced body fluids) and/or imbalance of the body’s chemicals and minerals circulating in the blood are the most important acute harmful effects of nausea and vomiting. The doctor will measure vital signs (pulse, blood pressure, temperature), perform a physical examination to look for signs of dehydration, check levels of chemicals in the blood, test the kidney and liver with blood tests, and sometimes order testing of the heart. Treatment with intravenous fluids, sometimes with added chemicals (such as Ringer’s lactate, fluids with added potassium or magnesium), and medications to reduce nausea and vomiting may be used.
When nausea and vomiting last for a long time, there may be weight loss or malnutrition. Feeding into the intestines (enteral nutrition) or sometimes directly into a large vein (parenteral nutrition) may be needed.
Violent retching or vomiting can cause painful bruises or tears in the abdominal wall muscles, with pain and soreness to touch. Sometimes tears develop in the lining where the swallowing tube joins the stomach, called Mallory-Weiss tears. These tears may bleed, and the vomit may contain blood, or stools may turn black and sticky. Very rarely, the entire wall of the esophagus can tear, with escape of stomach contents into the chest or abdomen, called Boerhaave’s syndrome. This is a serious condition and can lead to abscess formation or fluid collection, typically around the bottom of the left lung.
After talking to you and examining you, your doctor will often know why you have nausea and vomiting. Your doctor will try to understand what was going on before you started having nausea and vomiting:
If the diagnosis is not made after the doctor takes a history and performs an examination, some of the following tests may be requested by your doctor:
If the cause of nausea and vomiting is not clear after a thorough search and if the symptoms are not controlled with standard therapy, psychological tests and evaluation or psychiatric consultation are considered. Psychogenic vomiting and eating disorders such as anorexia nervosa or bulimia can also cause long-standing nausea and vomiting.
The treatment of nausea and vomiting depends on the cause, but certain general measures are suitable for any patient with nausea and vomiting.
Nausea and vomiting with a known cause such as motion sickness, chemotherapy, or surgical anesthesia can be prevented with medicines taken just before the causative event or medication. Nausea and vomiting from medicines and toxins improve when the drug or toxin is stopped. Morning sickness of pregnancy improves as the pregnancy progresses or with delivery of the baby. Nausea and vomiting from chronic disorders such as functional problems, psychiatric disorders, endocrine disorders or cancer may be difficult to cure and may need chronic medications to control the symptoms. If nausea and vomiting are related to an infectious or inflammatory condition, symptoms will generally go away completely with treatment of the primary condition.
Chandra Prakash, MD, MRCP, Washington University, St. Louis, MO – Published June 2005.
Ryan F. Porter, MD, and C. Prakash Gyawali, MD, MRCP, FACG, Washington University, St. Louis, MO – Updated January 2010.
Beth Huebner, MD, FACG, and C. Prakash Gyawali, MD, MRCP, FACG, Washington University, St. Louis, MO – Updated May 2022.
