Tropisetron or ondansetron compared with placebo for prevention of postoperative nausea and vomiting

In a prospective, randomized, double-blind, placebo-controlled, multicentre study, the efficacy of prophylactic tropisetron (2 mg) or ondansetron (4 m g)for the prevention of post-operative nausea and vomiting after abdominal or non-abdominal surgery with general balanced anaesthesia was studied in 8 42 ASA I-III patients. In patients undergoing abdominal surgery, ondansetro n and tropisetron reduced the frequency of emetic episodes compared with th e placebo (29%, 30% vs. 42% respectively). In men, neither tropisetron nor ondansetron had an effect different from the placebo, whereas in women both drugs led to lower rates of emetic episodes and nausea. In comparison with abdominal surgery, fewer patients in the non-abdominal surgery subgroup ha d emetic episodes (42% us. 23% in the placebo group). However, neither trop isetron nor ondansetron was significantly different from the placebo in thi s patient subgroup. In conclusion, for patients at increased risk of post-o perative nausea and vomiting, a prophylactic therapy at the lowest effectiv e dose with tropisetron or ondansetron may be useful.