Objective: To compare the efficacy of tropisetron and chlorpromazine for prevention of nausea and vomiting which occur after cytotoxic therapy. Study Design: Thirty cases, who were administered combined cisplatine and cyclophosphamide chemotherapy for advanced malignant epithelial ovarian neoplasm, were included in the study. Anti-emetic efficacy and adverse effects of tropisetron given during a total of 80 chemotherapy administrations and chlorpromazine given during a total of 70 chemotherapy administrations in these cases, were evaluated prospectively. Results: Considering the prevention of vomiting, tropisetron was observed to achieve complete control in 70.0 %, major control in 21.3 %, minor control in 3.7 %, and no control in 5.0 % of the chemotherapy administrations, while these rates were found as 14.3 %, 17.1%, 35.7 % and 32.9 % respectively for chlorpromazine. The succes rate of tropisetron for prevention of vomiting (complete and major control) was observed to be significantly higher than that of chlorpromazine (p<0.01). Moreover, tropisetron (5.0 %) was observed to prevent severe nausea more effectively than chlorpromazine (15.3 %) (p<0.05). When the adverse effects developed after these two medications were compared, sedation, mouth dryness, headache, tremor and dizziness were observed more frequently after chlorpromazine treatment (p<0.01). Conclusion: Compared to chlorpromazine, tropisetron was suggested to be more efficient and safe medication for prevention of nausea and vomiting, developing after cytotoxic therapy.