Cyclic vomiting syndrome (NORD)

00:00 / 00:00



Cyclic vomiting syndrome (NORD)

Information for patients and families

Information for patients and families

Information for patients and families

Information for patients and families


Cyclic vomiting syndrome, or CVS for short, is a disorder characterized by recurrent or cyclic episodes of severe nausea and vomiting. CVS can occur at any age, but is typically more common and severe in children.

Episodes of nausea and vomiting may last for a few hours to several days. They generally have sudden onset, resolve for a period of time, and are similar each time.

In some people, especially adults, nausea and vomiting may continue between episodes,but the intensity is far less severe than during episodes.

Episodes may occur a few times a year or as frequently as several times a month. Episodes may return like clockwork, and monthly episodes are common. They can occur at times of stress, or be apparently random.

During an episode, vomit can be bilious, appearing green or yellow. Children may experience bouts of projectile vomiting as frequently as four or more times per hour, which can potentially lead to dehydration and electrolyte imbalances, involving sodium and potassium.

Episodes can also be associated with severe abdominal pain, retching, and diarrhea, as well as decreased appetite and weight loss.

Some individuals may also experience migraine-like symptoms, like headaches and sensitivity to light and sound, as well as fever, dizziness, a lack of energy, and pallor.

In severe cases, an individual can become incapacitated and unable to walk or talk until the episode resolves. The exact cause of CVS is still unknown, but it seems to have many contributing factors.

The nervous system is thought to play a role. Nerves deliver messages throughout the body, including between the brain and gut, to coordinate functions.

Most individuals with CVS have migraines or a family history of migraines. In fact, CVS is sometimes called “abdominal migraine”.

Gastrointestinal motility may also have a role. The gastrointestinal tract has a layer of smooth muscles, which normally help push food, liquid, and gas from the esophagus down to the rectum.


Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent, sudden episodes of severe nausea and vomiting. These episodes can last for hours, days, or weeks and are not associated with other illnesses or injuries. Between episodes, people with CVS feel entirely normal.

The cause of CVS is unknown, but it may be related to problems with the autonomic nervous system or changes in the levels of certain chemicals in the blood. Some people with CVS have a family history of the condition. CVS usually starts in childhood, mainly affecting children between the age of 3 to 7 years. It often resolves by adolescents, but it may persist in some individuals until adulthood.


Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Cookies are used by this site.

USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.