Ondansetron Injection –  Ondansetron is a medication that belongs to the class of medicines called 5-HT3 receptor antagonists that blocks the actions of the chemical messengers in the body that prevents nausea and vomiting that may be generated by cancer chemotherapy, surgeries, or radiation treatment. Ondansetron also has the ability to reduce anxiety and depression in a person as it is an anti-sickness medicine. It is available with the brand name ONON at Mestra Pharma.