Prevention of chemotherapy-induced emesis: the state of the art.

In the last decade research on antiemetic therapy has determined relevant advances in the prevention of chemotherapy-induced emesis. In fact, 70-80% of patients submitted to highly or moderately emetogenic drugs achieve complete protection against vomiting during the first cycle of chemotherapy. In the prevention of acute emesis induced by a high single dose (> or 50 mg/m2) or a low dose (20-40 mg/m2) of cisplatin repeated for 4-5 days, a combination of ondansetron plus dexamethasone was shown to be more efficacious and less toxic than the combination of high dose metoclopramide plus dexamethasone plus diphenhydramine. Few studies have been performed for the prevention of delayed emesis induced by cisplatin. At present, the combination of oral dexamethasone plus metoclopramide seems to offer the best protection and should be considered the treatment of choice. For the prevention of acute emesis induced by moderately emetogenic drugs, corticosteroids (dexamethasone and methylprednisolone) and the new 5-HT3 receptor antagonists have a similar efficacy and a low toxicity. On a cost basis, corticosteroids must be considered the drug of choice while 5-HT3 receptor antagonists should be used only in patients refractory to corticosteroids or in those who cannot tolerate them.