It is a potent higly selective antagonist at the 5 hydroxytryptamine receptors sbtype 3 .
It can effectively control vomiting due to anticancer drugs as well as raitherapy .unlike metocloprmide ,
Ondansetron is not a lopomide antagonist and doesnot cause dystonia or extra pyramidal effects.
It is a carbazole with causes antinauseant and antiemtic effects by selective and competitive blockade of the 5ht3 receptors .
Vomiting and nausea associated with cytoxic radiotherapy and chemotherapy ,prophylaxis and treatment of postoperative vomiting andnausea