Antiemetic agents.

Despite major progress in the treatment of chemotherapy-induced emesis, nearly one third of patients undergoing cisplatin-based regimens still experience emesis within the first 24 hours of chemotherapy. An adequate treatment of delayed and anticipatory emesis remains to be determined. For highly emetogenic chemotherapy, the combination of ondansetron and dexamethasone is superior to dexamethasone alone and protects most patients. For moderately emetogenic regimens, the high level of complete control that can be achieved with the use of standard antiemetics is comparable to that obtained with ondansetron. This would suggest that, to reduce the cost of antiemetic therapy, ondansetron can be limited in case of failure of standard therapy. Delayed emesis remains poorly controlled with no difference between metoclopramide, dexamethasone, ondansetron, and placebo. Although some data suggest an improved efficacy when combining ondansetron with dexamethasone, convincing confirmatory studies are needed.