Cyclic vomiting syndrome (US English) or cyclical vomiting syndrome (UK English) (CVS) is a condition whose symptoms are recurring attacks of intense nausea, vomiting and sometimes abdominal pain and/or headache. CVS can affect both children and adults. It was first described in the 19th century with one of the earliest references being that of Samuel Gee in 1882. Onset of the condition is possible at any age. Why anyone develops it is not clear. There is a strong suggestion of maternal inheritance.
CVS differs from other forms of vomiting as it is an acute condition. Sufferers may vomit six times an hour and an episode may last from 1 day to over 2 weeks, between episodes the sufferer is usually otherwise normal and healthy. The median duration of an episode is 41 hours (Li & Fleisher 1999). In approximately half of sufferers the attacks, or episodes, occur in a time related manner. Each attack is stereotypical, i.e. in any given individual their timing, frequency and severity of attacks is similar. Episodes may happen every few days or every few months. For some there is not a pattern in time that can be recognised. Some people find it hard to conceive how anyone can vomit after that length of time, as the stomach will have emptied after the first few emeses. However, acid, bile and, if the vomiting is severe, blood, may be vomited. The physical act of vomiting continues but the volume of material in the vomit is less. Some sufferers have a warning of an attack, they may experience a prodrome, usually intense nausea and pallor. The majority of sufferers, but not all can identify "triggers" that may precipitate an attack. The most common are infections (such as colds) and psychological stress both positive and negative e.g. an upcoming pleasant event such as a holiday or birthday may trigger an attack.
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Cyclic Vomiting Syndrome - CVS is a childhood disorder characterized by bouts of vomiting that last from a few hours to several days.
Meta Description: [ Desribes the four phases of cyclic vomiting syndrome and the current treatment options available. Outlines the complications associated with the disorder and provides additional resources ]
Cyclic Vomiting Syndrome Association- USA/Canada - Provides support, information and latest medical research about CVS, abdominal migraine, nausea, vomiting, and the International CVS Center.
Cyclical Vomiting Syndrome - UK Charity supporting research, education, and sufferers of CVS.
Laura's Page - I'm the Kid's Page Coodinator of the Cyclical Vomiting Syndrome Association, CVSA, Code V Newsletter.