What is the active ingredient in Onda?
                                
                                
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                                    4 min read                                
                            
                                The active ingredient in the anti-nausea medication known as Onda is ondansetron, a selective 5-HT3 receptor antagonist. This ingredient works by blocking the action of serotonin, a natural substance in the body that can trigger the reflex for nausea and vomiting.