We estimated the cost-utility of palonosetron-based therapy compared with generic ondansetron-based therapy throughout four cycles of anthracycline and cyclophosphamide for treating women with breast cancer. We developed a Markov model comparing six strategies in which ondansetron and palonosetron are combined with either dexamethasone alone, dexamethasone plus aprepitant following emesis, or dexamethasone plus aprepitant up front. Data on the effectiveness of antiemetics and emesis-related utility were obtained from published sources. Relative to the ondansetron-based two-drug therapy, the incremental cost-effectiveness ratios for the palonosetron-based regimens were $115,490/quality-adjusted life years (QALY) for the two-drug strategy, $199,375/QALY for the two-drug regimen plus aprepitant after emesis, and $200,526/QALY for the three-drug strategy. In sensitivity analysis, using the $100,000/QALY benchmark, the palonosetron-based two-drug strategy and the two-drug regimen plus aprepitant following emesis were shown to be cost-effective in 39% and 26% of the Monte Carlo simulations, respectively, and with changes in values for the effectiveness of antiemetics and the rate of hospitalization. The cost-utility of palonosetron-based therapy exceeds the $100,000/QALY threshold. Future research incorporating the price structure of all antiemetics following ondansetron's recent patent expiration is needed.