Comparison of the Efficacy of Amitriptyline and Topiramate in Prophylaxis of Cyclic Vomiting Syndrome

OBJECTIVES: Cyclic vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder with no certain treatment. We aimed to compare the efficacy of amitriptyline and topiramate on prophylactic therapy of CVS. MATERIALS & METHODS: This randomized clinical trial (registration number: IRCT2015102316844N2) was conducted during 2016 in Isfahan, central Iran. The inclusion criteria were CVS patients (based on Rome III) aging 3-15 yr with normal physical examination, no metabolic disorder, and no gastrointestinal obstruction or renal impairment. Recruited patients were divided into two groups of amitriptyline (1 mg/kg/d) and topiramate (1-2 mg/kg/d) and were followed for 3-months. The outcome was evaluated by comparing severity of attacks (monthly frequency and duration of attacks) before and after intervention. RESULTS: Thirty-six children entered each group and two patients left the amitriptyline group. Patients and disease characteristics were similar between groups before intervention (P>0.05). The frequency of attacks (standard deviation) after intervention in amitriptyline and topiramate group was 0.91 (0.40) and 1.07 (0.55), respectively (P=0.368) and the duration of attacks (SD) after intervention were 3.43 (2.46) and 4.90 (3.03), respectively (P=0.017). Twenty-three patients (68%) in amitriptyline group and 14 patients (39%) in topiramate group stopped having attacks after intervention (P=0.016). CONCLUSION: Amitriptyline is a better choice to reduce severity of CVS attacks compared to topiramate, in a short-term evaluation. Studies with longer follow-up are required to investigate these findings in a longer period.