The effect of oral ondansetron on QT interval in children with acute gastroenteritis; a retrospective observational study

Background In mildly to moderately dehydrated patients with acute gastroenteritis (AGE), oral rehydration therapy (ORT) is the treatment of choice. Though ondansetron is a very effective antiemetics and leads to succeed ORT, there have been reports QT prolongation in patients using it. We investigated the effect of oral ondansetron on QT interval in mildly to moderately dehydrated children with AGE. Methods This retrospective observational study was conducted in a single pediatric emergency department (ED) of a tertiary university hospital. We collected the medical records of patients with a primary diagnosis of AGE who received oral ondansetron and underwent an electrocardiogram between January 2017 and June 2018. A pediatric emergency physician calculated the corrected QT interval (QTc) by Bazett’s method, and the calculations were reviewed by a pediatric cardiologist. QTc values before (preQTc) and after (postQTc) ondansetron administration were analyzed. ΔQTc was calculated as the change from preQTc to postQTc. We also investigated any cardiac complications from oral ondansetron. Results Total 80 patients were included. The mean age of the patients was 53.31 ± 32.42 months, and 45% were male. The mean dose of oral ondansetron was 0.18 ± 0.04 mg/kg. The mean interval from administration of ondansetron to performance of the electrocardiogram was 65 ± 26 min. The mean preQTc was 403.3 ± 24.0 ms, and the mean postQTc was 407.2 ± 26.7 ms. Two patients had a preQTc ≥460 ms, and one patient had a postQTc ≥460 ms. ΔQTc was ≥30 ms in seven patients (8.8%). No ΔQTc was ≥60 ms. No pre- or postQTc was ≥500 ms. No patient had a fatal cardiac arrhythmia after taking ondansetron. Conclusion Oral administration of a single dose of ondansetron in children with AGE did not cause high-risk QTc prolongation or fatal arrhythmia.

Oral ondansetron for paediatric gastroenteritis in primary care: a randomised controlled trial

Background: Acute gastroenteritis affects almost all children younger than 5 years. Due to vomiting the standard oral rehydration therapy (ORT) treatment is less effective. In secondary care, ondansetron was found to be effective in reducing vomiting. Aim: To determine the effectiveness of adding oral ondansetron to care-as-usual on vomiting in children with acute gastroenteritis attending out-of-hours primary care. Design and setting: A pragmatic randomised controlled trial with a follow-up of 7 days, at three out-of-hours primary care centres. Method: Inclusion criteria: 1) age 6 months to 6 years, 2) acute gastroenteritis diagnosed by a general practitioner, 3) at least four reported episodes of vomiting in the 24 hours before presentation, 4) at least one reported episode of vomiting in the 4 hours before presentation, and 5) written informed consent from both parents. The control group received care-as-usual (ORT). The intervention group received care-as-usual plus one dose of oral ondansetron (0.1 mg/kg). Results: In total, 194 children were included for randomisation. One dose of oral ondansetron decreased the proportion of children who continued vomiting within 4 hours from 42.9% to 19.5%, with an odds ratio of 0.37 (95% CI = 0.20–0.72, NNT 4). Ondansetron also decreased the number of vomiting episodes within 4 hours, incidence rate ratio of 0.51 (95% CI, 0.29-0.88), and improved overall parental satisfaction with treatment (p = 0.027). Conclusions: Ondansetron decreased vomiting and increased parental satisfaction in children with acute gastroenteritis. We were not able to show an increased ORT intake or decrease in referral rate.

Cost-effectiveness of oral ondansetron for children with acute gastroenteritis in primary care: a randomised controlled trial

Background: Acute gastroenteritis is a common childhood disease with substantial medical and indirect costs, mostly because of referral, hospitalization and parental absence from work. Aim: To determine the cost-effectiveness of adding oral ondansetron to care-as-usual for children with acute gastroenteritis in out-of-hours primary care. Design and setting: A pragmatic randomised controlled trial at three out-of-hours primary care centres, with a follow-up of 7 days. Method: Inclusion criteria were: 1) age 6 months to 6 years; 2) diagnosis of acute gastroenteritis; 3) at least four reported episodes of vomiting 24 hours before presentation, whereof; 4) at least one in the 4 hours before presentation; and 5) written informed consent from both parents. Children were randomly allocated in a 1:1 ratio to either care-as-usual (oral rehydration therapy) or care-as-usual plus one dose of 0.1 mg/kg oral ondansetron. Results: In total, 194 children were included for randomisation. One dose of oral ondansetron decreased the proportion of children who continued vomiting within the first 4 hours from 42.9% to 19.5%, with an odds ratio of 0.4 (95% CI = 0.2–0.7, NNT 4). Total mean costs in the ondansetron group were 31.2% lower (€488 vs €709), and the total incremental mean costs for an additional child free of vomiting in the first 4 hours was −€9 (95% confidence interval, −€41 to €3). Conclusion: A single oral dose of ondansetron for children with acute gastroenteritis, given in out-of-hours primary care settings, is both clinically beneficial and cost-effective.

Treatment with Oral Ondansetron for Ultramarathon-Associated Nausea: The TOO FUN Study

Nausea and vomiting are common for runners during ultramarathons and often contribute to non-finishes. We aimed to determine the efficacy of ondansetron, a commonly used antiemetic, to treat nausea and vomiting in runners during an ultramarathon. Runners who had a previous history of frequent nausea or vomiting during races and entered in 160, 80, and 55 km ultramarathons in 2018 and 2019 were randomized in a double-blind fashion to 4 mg ondansetron or placebo capsules to use if they developed nausea or vomiting during the race with the ability to take three additional doses. Study participants completed a post-race online survey to assess medication use and efficacy. Of 62 study participants, 31 took either ondansetron (20) or placebo (11). In this small study, there were no group differences in those reporting any improvement in nausea and vomiting (p = 0.26) or in the amount of improvement (p = 0.15). We found no evidence that ondansetron capsules improve nausea and vomiting during ultramarathons.

Oral Versus Intramuscular Ondansetron for Reducing Vomiting in Children with Acute Gastroenteritis: A Single-Blind Randomized Clinical Trial

Background: Acute gastroenteritis is one of the most common diseases in children with a high rate of nausea and vomiting. Drugs such as ondansetron are used to treat vomiting. Objectives: The aim of the study was to compare the success rate of oral vs intramuscular ondansetron to reduce vomiting in children with acute gastroenteritis. Methods: A single-blind randomized clinical trial study was conducted on 100 children with acute gastroenteritis. Two groups of patients were created; one group received an intramuscular injection of ondansetron and the other received oral ondansetron. The vomiting rate, hospitalization, and side effects were evaluated 30 minutes, 4, and 48 hours after drug administration. Results: Fifty-nine (59%) boys with a mean age between 3.07 ± 2.20 years were included. There were no significant differences between the groups in terms of age, weight, and rate of vomiting before the treatment was launched. No significant difference between the drug administration route and the outcome of vomiting during the first half, 4, and 48 hours after receiving the drug was found either. Conclusions: The study showed that the success rate of oral ondansetron did not vary significantly compared to intramuscular injection in terms of reducing the vomiting rate in children with acute gastroenteritis.