Cancer Chemotherapy-induced Nausea and Vomiting
Ondansetron is used orally or IV for the prevention of nausea and vomiting associated with emetogenic cancer chemotherapy. The drug is used IV with initial and repeat courses of emetogenic cancer chemotherapy, including high-dose cisplatin therapy. Ondansetron is used orally with highly emetogenic cancer chemotherapy (including cisplatin at a dosage of 50 mg/m or greater). Ondansetron also is used orally with initial and repeat courses of moderately emetogenic cancer chemotherapy. The drug has been used effectively for the prevention of chemotherapy-induced emesis in patients receiving cisplatin alone or in combination with other antineoplastic agents and in those receiving other antineoplastic regimens (e.g., cyclophosphamide plus fluorouracil, doxorubicin, methotrexate, and/or vincristine) that did not include cisplatin.
To prevent chemotherapy-induced nausea and vomiting associated with highly emetogenic chemotherapy regimens (including an anthracycline plus cyclophosphamide), the American Society of Clinical Oncology (ASCO) currently recommends a 3-drug antiemetic regimen consisting of a neurokinin-1 (NK1) receptor antagonist (e.g., either oral aprepitant or IV fosaprepitant dimeglumine), a type 3 serotonin (5-HT3) receptor antagonist (e.g., dolasetron, granisetron, ondansetron, palonosetron, ramosetron [not commercially available in the US], tropisetron [not commercially available in the US]), and dexamethasone. ASCO states that the oral, fixed-combination of netupitant and palonosetron plus dexamethasone is an additional antiemetic treatment option in this setting.
For patients receiving moderately emetogenic chemotherapy regimens, ASCO recommends a 2-drug antiemetic regimen preferably consisting of palonosetron and dexamethasone. If palonosetron is not available, a first-generation 5-HT3 receptor antagonist (preferably granisetron or ondansetron) may be substituted. Limited evidence suggests that aprepitant may be added to this regimen; in such cases, ASCO states that any of the 5-HT3 receptor antagonists is appropriate.
For patients receiving chemotherapy regimens with a low emetogenic risk, ASCO recommends administration of a single dose of dexamethasone prior to chemotherapy.
In patients receiving chemotherapy regimens with a minimal emetogenic risk, antiemetics should not be routinely administered prior to or following chemotherapy.
Postoperative Nausea and Vomiting
Ondansetron is used orally or IV for the prevention of postoperative nausea and vomiting. Oral or IV ondansetron has been used effectively to prevent nausea and vomiting in surgical patients where nausea and vomiting must be avoided postoperatively; IV ondansetron also has been used effectively to prevent further episodes of nausea and vomiting in patients who did not receive prophylactic antiemetic therapy and developed postoperative nausea and/or vomiting. Studies of oral ondansetron for the prevention of postoperative nausea and vomiting to date have included only women undergoing inpatient surgical procedures; no studies have been performed in males. Controlled studies comparing oral versus IV administration of ondansetron have not been performed to date. The manufacturer states that as with other antiemetics, routine prophylaxis with ondansetron is not recommended in patients in whom there is little expectation that nausea and/or vomiting will occur postoperatively. However, use of the drug is recommended for patients in whom nausea and/or vomiting must be avoided postoperatively, even when the anticipated incidence of such nausea and/or vomiting is low.
Radiation-induced Nausea and Vomiting
Ondansetron is used orally for the prevention of radiation-induced nausea and vomiting. The drug has been used effectively to prevent nausea and vomiting in patients receiving total body irradiation or single high-dose fraction or daily fractionated radiation to the abdomen.