Palonosetron is an antiemetic agent that is a type of 5HT3 receptor antagonist. This group of agents suppresses nausea and vomiting by inhibiting the binding of serotonin to 5HT3 receptors, which can be found in the chemoreceptor trigger zone in the central nervous system. An oral formulation of this medication was studied for its effectiveness in preventing chemotherapy-induced nausea and vomiting in patients with cancer.