Palonosetron is an anti-sickness medicine, also known as an antiemetic. It is a serotonin receptor antagonist. It is prescribed to stop you from feeling sick (nauseated). It works by blocking the effect of a naturally produced chemical in your body, called serotonin. Serotonin is also referred to as 5HT3.
This is a companion discussion topic for the original article at https://patient.info/medicine/palonosetron-to-prevent-nausea-and-vomiting-after-chemotherapy