Olanzapine as an antiemetic in refractory nausea and vomiting in advanced cancer.

Nausea and vomiting are difficult symptoms to manage in patients with advanced cancer. Several classes of antiemetics are available, including phenothiazines, butyrophenones, substituted benzamides and selective serotonin antagonists, as well as corticosteroids. Most patients will respond to either single agents or combinations that frequently include corticosteroids. A minority of patients will have nausea that fails to respond. The atypical antipsychotic, olanzapine, relieves nausea in some patients failing to respond to the usual antiemetics. Two case reports are presented and the rationale for olanzapine's benefit is discussed.