Summary In 1983, Coates conducted a survey that ranked the side-effects perceived by patients receiving chemotherapy in the order of their severity. Vomiting and nausea were found to be the two most distressing side-effects. They have an impact on quality of life and compliance with treatment. The development of 5HT3 antagonists has been a major step forward in the prevention and treatment of chemotherapyinduced nausea and vomiting. Presently, these antiemetics are routinely used as concomitant therapy in emetogenic chemotherapy regimens. The purpose of this study was to evaluate the impact of 5HT3 antagonists on patient perceptions of the side-effects of chemotherapy. Coates' survey was replicated in patients who received 5HT3 antagonists for acute nausea and vomiting resulting from emetogenic chemotherapy. Patients received the survey to identify those physical and non-physical side-effects that they attributed to chemotherapy and were asked to rank the five most distressing side-effects. Of the 197 patients who consented to take part in the study, 181 were evaluable. Nausea, hair loss and vomiting were described as the three most distressing side-effects of chemotherapy. Eighty per cent of all the patients actually experienced nausea and 57% experienced vomiting. Hair loss appeared to be more distressing to women (P < 0.001) but, in other aspects, gender, age and marital status did not influence the ranking of the three most distressing side-effects. Constipation was ranked as 6th and was not identified as a distressing side-effect in 1983. Nausea and vomiting remain to be the first and third most distressing side-effects of chemotherapy, even though the incidence and severity of acute nausea and vomiting are now significantly reduced.Keywords: chemotherapy; nausea; vomiting; side-effects; serotonin antagonists Nausea and vomiting have been reported by patients, nurses and physicians as the most distressing side-effects of chemotherapy (Coates et al, 1983;Love et al, 1989;Pritchard, 1989;Cooper, 1992;Martin, 1992; Youngblood et al, 1994). The introduction of the 5HT3 antagonists Tropisetron, Ondansetron and Granisetron have significantly reduced the incidence of these distressing sideeffects. Physicians and nurses have observed that 5HT3 antagonists have contributed to an improvement of quality of life and compliance with treatment (Seynaeve et al, 1991a). However, the impact of these new drugs on patients' perceptions of chemotherapy-induced side-effects has not yet been investigated (Manson et al, 1993). Unfortunately, some health care workers extrapolate data on the improvement of antiemetic efficacy in the phase of acute emesis to represent the total experience of emesis in treated patients. They tend to believe that a decrease in the incidence and severity of acute emesis reduces the patients' distress accordingly. This might not be the case (Love et al, 1989;Bliss et al, 1992;Schmoll, 1992;Jansen et al, 1993; de Wit et al, 1996) as delayed emesis remains a serious problem. Therefore, we believed a reas...