Our findings, together with those of previous studies, suggest that prophylaxis with concomitant dexamethasone and ramosetron has a potent antiemetic effect on early PONV which is not provided by ramosetron alone. Meanwhile, our findings also indicate that ramosetron alone reduced PONV effectively during the 6- to 72-hour period after TKA in patients who are at high risk for PONV (Table 1). Therefore, although concurrent dexamethasone and ramosetron prophylaxis did not show superior antiemetic efficacy during the 6- to 72-hour period compared with ramosetron alone, our findings suggest concurrent dexamethasone and ramosetron prophylaxis is effective in reducing PONV during the 72-hour period after TKA in patients who are at high risk for PONV.