Ondansetron IV is prescribed to treat vomiting associated with cytotoxic chemotherapy as well as radiotherapy. Offered medication belongs to serotonin 5-HT3 receptor antagonist. This injection blocks functions of serotonin in body to avoid the sensation of vomiting. This injection is recommended for children belonging to more than or equal to 6 months of age. Dosage of this intravenous injection varies in case of child patient and adult patient. Ondansetron IV needs to be administered into vein only after consultation with doctor.