The management of cyclic vomiting syndrome: a systematic review.

Cyclic vomiting syndrome (CVS) is a rare abnormality of the neuroendocrine system that affects 2% of children. It is a frequently missed diagnosis in the emergency department and may require a number of emergency department visits before the diagnosis is made. The objectives of this review are to identify the clinical features that suggest a diagnosis of CVS and to review the literature on its management. The MEDLINE and EMBASE databases were searched from January 1948 to October 2011 using the keywords 'Cyclic' or 'Vomiting'. Papers were excluded if they did not follow the consensus guidelines or if they were case reports. This review analysed 1093 cases of cyclic vomiting in 25 papers that fulfilled the inclusion criteria. All except one paper were retrospective studies. The size of these cohort studies ranged from three to 181 patients, with a mean patient size of 29. This review found that over 40% of patients have headaches/migraines, with associated anxiety and depression in ≈ 30% of cases. There is a family history of headaches/migraines in 38.9%, and this association was much stronger in the adult CVS cohort compared with the paediatric cohort. Compared with paediatric CVS, adults have a longer duration of attacks and they occur more frequently (5.9 vs. 3.4 days, 14.4 vs. 9.6 episodes/year). Limited data are available on the treatment of the acute phase of CVS, but in adults, sumatriptan has been shown to be effective. For prophylactic treatment, tricyclics are effective in both adult and paediatric CVS, with a clinical response in 75.5 and 67.6% of patients, respectively, in nonplacebo-controlled cohort studies. Furthermore, propranolol has been shown to be useful in children. CVS is an intractable illness with a major impact on the patient's quality of life. There is a long duration between the onset of symptoms and the diagnosis of the condition. There is a high association with headaches/migraines and anxiety/depression. The symptoms are more severe in adult-onset CVS. Tricyclic antidepressants have good efficacy in reducing the frequency/duration or the intensity of attacks. There is limited evidence on the acute management of CVS.