Cyclic vomiting syndrome in pediatric population: characteristics and prophylactic response to cyproheptadine

Background: The aim of this study was to investigate the features of cyclic vomiting syndrome (CVS) in a pediatric cohort and assess the safety and efficacy of cyproheptadine regardless of age. Methods: This retrospective, monocentric study enrolled children diagnosed with CVS. After collecting data from the medical records, a telephone-based questionnaire interview with the caregivers was conducted to obtain missing or unclear data. Prodromal symptoms, triggers, and comorbidities were analyzed. The safety and efficacy of cyproheptadine were evaluated in the entire patient cohort and compared between children under 5 years old and those 5 years of age or older. Results: A cohort of 24 subjects with CVS were included. Prodromal symptoms were reported in 45.8%, triggers in 33.3%, and comorbidities in 58.3% of patients. Migraine was present in 54% of the patients. Cyproheptadine was prescribed to 15 of the 24 patients (62.5%), with 40% and 80% achieving a reduction in the frequency of vomiting clusters of over 75% after a median duration of 6.03 and 12.13 months respectively. Prophylactic therapy did not provide any benefit to 20% of the patients. No statistically significant differences were found in vomiting features or cyproheptadine response between children above and below 5 years, except for a negative correlation between age and the presence of diarrhea during CVS episodes. No serious adverse effects were reported. Conclusions: Assessment of prodromes, triggers, and comorbidities aids in CVS diagnosis in children. Cyproheptadine is effective and safe for the management of CVS regardless of age.