What Is Cyclical Vomiting Syndrome (CVS)?

CVS is an unexplained disorder of children and adults that was first described by Dr. S. Gee in 1882. The condition is characterized by recurrent, prolonged attacks of severe nausea, vomiting, and prostration with no apparent cause. In some, there is severe abdominal pain. Vomiting occurs at frequent intervals for hours or days (1-4 days, most commonly). The episodes tend to be similar to each other in symptoms and duration, and are self-limited with return of normal health between episodes.

What is CVS?

The above video was created by Linda Fox with Seth Dearborn and Kari Christian.


CVS can begin at any age. It can persist for months, years, or decades. Episodes may recur several times a month or several times a year. Females are affected slightly more than males. The person may be prone to motion sickness, and there is often a family history of migraine. There is a high likelihood that children’s episodes will be replaced by migraine headaches during adolescence.


Episodes may begin at any time, but often start during the early morning hours. There is relentless nausea with repeated bouts of vomiting or retching. The person is pale, listless, and resists talking. They often drool or spit and have an extreme thirst. They may experience intense abdominal pain and less often headache, low-grade fever, and diarrhea. Prolonged vomiting may cause mild bleeding from irritation of the esophagus. One mother aptly described her child’s state during the episode as a “conscious coma.” The symptoms are frightening to the person and family, and can be life-threatening if delayed treatment leads to severe dehydration.


CVS has been difficult to diagnose because it is infrequently recognized and is often misdiagnosed as stomach flu or food poisoning. There are as yet, no blood tests, x-rays, or other specific procedures used to diagnose the disorder. The diagnosis is made by careful review of the patient’s history, physical examination, and lab studies to rule out other diseases that may cause vomiting similar to that found with CVS.


Patients may not know exactly what triggers their attacks; however, many patients identify specific circumstances that seem to bring on their episodes. Colds, flus and other infections, intense excitement (birthdays, holidays, vacations), emotional stress, and menstrual periods are the most frequently reported triggers. Specific foods or anesthetics may also play a role.


Treatment is generally supportive, with much importance placed on early intervention. A dark quiet environment is critical for sleep. Hospitalization and IV fluid replacement may be necessary. Medication trials sometimes succeed in finding something to prevent, shorten, or abort episodes. It is important to work with a physician who does his/her best to understand CVS and is supportive.

Long-Term Treatment

The foundation of long-term management involves a responsive collaborative doctor-patient-family relationship, sensitive to stresses caused by the illness and to triggers such as feelings and attitudes that may pre-dispose the patient to attacks. Consistent and accessible physician care by a care coordinator who understands and communicates the nature of CVS, regardless of specialty, is vital to the family’s well-being. Connections with the Cyclic Vomiting Syndrome Association, a family and professional network, can do a great deal toward healing a family that has been in doubt and despair for years.

Related Terms

abdominal migraine, bilious attacks, periodic syndrome, recurrent vomiting

Learn More about CVS

The above video was created by Seth Dearborn and Kaare Christian.

Participants include: Victoria McCabe, James O’Reilly, Kari Christian, Anne Grechanik and Robin Raskin.