HTR3A and gastroenteritis: The current study revealed that ondansetron demonstrates superior efficacy compared to domperidone and metoclopramide in alleviating vomiting in children with gastroenteritis, likely owing to its oral absorption and its role as a "serotonin 5-HT3 receptor antagonist." This mechanism involves suppressing the vomiting centers in the brain and inhibiting afferent depolarization of peripheral vagal nerves in the intestine, which can trigger emesis in gastroenteritis patients [12,23].