For persons receiving chemotherapy of high emetic risk , there is no group of patients for whom agents of lower therapeutic index are appropriate first-choice antiemetics .
In all patients receiving cisplatin and all other agents of high emetic risk , the two-drug combination of dexamethasone and aprepitant is recommended for the prevention of delayed emesis .
The Up date Committee no longer recommends the combination of a 5-HT3 serotonin receptor antagonist and dexamethasone for the prevention of delayed emesis after chemotherapeutic agents of high emetic risk .
PURPOSE To up date the 1999 American Society of Clinical Oncology guideline for antiemetics in oncology .
Efficacy of Oral Ondansetron, A Selective Antagonist of 5‐HT3 Receptors, in the Treatment of Nausea and Vomiting Associated with Cyclophosphamide‐Based Chemotherapies
We evaluated the efficacy and safety of oral ondansetron , a selective antagonist of 5-HT3 receptors , for the treatment of nausea and vomiting associated with  cyclophosphamide-based chemotherapy ( > 500 mg/m2 ) . In this trial 324 chemotherapy-naive cancer patients , mostly females with breast cancer , were r and omized to receive either placebo or ondansetron 1 mg , 4 mg , or 8 mg three times per day for 3 days . There were no differences in the doses of cyclophosphamide , doxorubicin , and methotrexate between the study groups . All ondansetron dose groups were superior to the placebo control group ( p < .001 ) for all measured efficacy parameters ( complete response , number of emetic episodes , therapeutic failures , need of rescue antiemetics ) . No emetic episodes were reported by 9 ( 12 % ) , 29 ( 37 % ) , 48 ( 64 % ) , and 47 ( 66 % ) of the placebo patients and the 1-mg , 4-mg , and 8-mg dose of ondansetron patients , respectively . Nausea was reduced and food intake was improved for all the ondansetron groups . A more severe emetic response was observed in patients receiving cyclophosphamide and doxorubicin combination chemotherapy . In this subgroup of patients . 66 % , 38 % . 25 % , and 16 % of the placebo group and 1-mg , 4-mg , and 8-mg ondansetron patients , respectively , required rescue anti-emetics . No significant toxic effects were observed in this study . A higher incidence of headaches and gastrointestinal complaints ( constipation , abdominal pain ) were observed in the three ondansetron groups . In conclusion , oral ondansetron is an effective and well-tolerated antiemetic treatment in the management of cancer patients receiving ambulatory cyclophosphamide-based chemotherapy .  These results support the view that serotonin and 5-HT3 receptors play an important role in cyclophosphamide-induced nausea and vomiting
For persons receiving chemotherapy of high emetic risk , there is no group of patients for whom agents of lower therapeutic index are appropriate first-choice antiemetics .
In all patients receiving cisplatin and all other agents of high emetic risk , the two-drug combination of dexamethasone and aprepitant is recommended for the prevention of delayed emesis .
The Up date Committee no longer recommends the combination of a 5-HT3 serotonin receptor antagonist and dexamethasone for the prevention of delayed emesis after chemotherapeutic agents of high emetic risk .
PURPOSE To up date the 1999 American Society of Clinical Oncology guideline for antiemetics in oncology .