Cyclic vomiting syndrome (US English) or cyclical vomiting syndrome (UK English) (CVS) is a condition whose symptoms are recurring attacks of intense nausea

Nausea

Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...

, vomiting

Vomiting

Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...

 and sometimes abdominal pain

Abdominal pain

Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. Making a definitive diagnosis of the cause of abdominal pain can be difficult, because many diseases can result in this symptom. Abdominal pain is a common problem...

 and/or headaches or migraine

Migraine

Migraine is a chronic neurological disorder characterized by moderate to severe headaches, and nausea...

s. Cyclic vomiting usually develops during childhood

Childhood

Childhood is the age span ranging from birth to adolescence. In developmental psychology, childhood is divided up into the developmental stages of toddlerhood , early childhood , middle childhood , and adolescence .- Age ranges of childhood :The term childhood is non-specific and can imply a...

 usually ages 3–7; although it often remits during adolescence

Adolescence

Adolescence is a transitional stage of physical and mental human development generally occurring between puberty and legal adulthood , but largely characterized as beginning and ending with the teenage stage...

, it can persist into adult life.
The average age at onset is 3–7 years, but CVS has been seen in infants who are as young as 6 days and in adults who are as old as 73 years.