The influence of perioperative analgesia modes on the prevalence of postoperative nausea and vomiting in day-case surgery patients is investigated in the article. The study involved 100 cases of unilateral phlebectomy under propofol and nitrous oxide anaesthesia, randomized by 4 groups with different perioperative analgesia modes of 25 patients each. In the first group fentanyl IV infusion was provided during surgery, in the second group it was amplified with ketoprofen 100 mg IV. In the third group sodium adenosintriphosphate IV infusion was provided for the whole surgery time, whereas the patients in the fourth group received 100 mg ketoprofen IV before it. Analgesic efficacy of all the four modes was equal, while ketoprofen administration aggravated and prolonged postoperative nausea and vomiting without influence on PONV morbidity.