[Clinical characteristics of cyclic vomiting syndrome and the therapeutic efficacy of chlorpromazine combined with promethazine].

Objective: To analyze the clinical characteristics of cyclic vomiting syndrome (CVS) in children and to evaluate the efficacy of chlorpromazine combined with promethazine in treating acute episodes. Methods: This retrospective cohort study analyzed the clinical data of 110 pediatric patients diagnosed with CVS at the Department of Gastroenterology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University from January 2015 to January 2025. General information and clinical manifestations were summarized. Based on the treatment regimens administered during acute phases, patients were divided into the promethazine plus chlorpromazine group and the ondansetron or omeprazole group. The clinical efficacy of the two regimens was compared by Mann-Whitney U test. Results: Among the 110 children with CVS, there were 63 males and 47 females. The age of onset was 6.5 (3.2, 8.5) years. Predisposing factors were identified in 17.3% (19/110) of the children, with dietary indiscretion (8 cases) and infection (5 cases) being the most common. All children experienced vomiting, with episode durations ranging from 1 to 10 days and inter-episode intervals ranging from 7 days to 6 months. In addition to vomiting, gastrointestinal symptoms included anorexia in 110 cases (100%), abdominal pain or abdominal discomfort in 79 cases (71.8%), diarrhea in 2 cases (1.8%); 21 children exhibited autonomic nervous system symptoms, including low-grade fever in 11 cases (10.0%), pallor in 7 cases (6.4%), elevated blood pressure in 2 cases (1.8%), excessive salivation in 1 case (0.9%). Nervous system symptoms occurred in 19 cases, manifesting as headache or dizziness (17.3%). Psychological disorders were present in 13 children. During acute episodes, 46 children received intramuscular chlorpromazine combined with promethazine. Their vomiting duration was 1 (1, 2) d, and no adverse reactions were observed. In contrast, 20 children who received intravenous drip ondansetron or omeprazole had a vomiting duration of 3 (3, 5) d. The vomiting duration in the chlorpromazine plus promethazine group was significantly shorter than that in the ondansetron or omeprazole group (Z=6.69, P<0.01). Conclusions: CVS in children is characterized by recurrent episodes. Vomiting is frequently accompanied by other gastrointestinal or autonomic symptoms. For acute episodes, chlorpromazine combined with promethazine is an effective and safe treatment.