Background: Postoperative nausea and vomiting (PONV) can affect up to 30% of patients. While the use of antiemetics for prophylaxis has been extensively reported there is less evidence of their efficacy for the treatment of PONV. Aim: To review the evidence and discuss the use of 5-hydroxytryptamine type 3 (5-HT 3 ) antagonists for the treatment of PONV in Australia. Method: A literature search was conducted to identify clinical studies evaluating the effects of 5-HT 3 antagonists in the treatment of PONV. Results: In four studies various doses of 5-HT 3 antagonists were compared and in five studies a single dose of 5-HT 3 antagonist was assessed against another antiemetic or placebo, or both. Conclusion: These studies indicate that 5-HT 3 antagonists are effective and safe in the treatment of PONV.