A randomised placebo controlled study with ondansetron in patients undergoing fractionated radiotherapy.

Background: There are few randomised studies comparing anti-emetic drugs for the prevention of nausea and vomiting in patients treated with fractionated radiotherapy. The aim of the study was to compare the anti-emetic efficacy of 8 mg dose ondansetron twice a day with placebo.

Materials And Methods: One hundred eleven patients who were to commence a course of 10 or more daily fractionated radiotherapy including the abdomen were included in the study. The patients recorded daily emesis, nausea and bowel habit and graded weekly symptoms of nausea, vomiting, diarrhoea and lack of appetite. The EORTC C30 questionnaire was completed.

Results: 67% of patients given ondansetron had complete control of emesis compared with 45% of patients with placebo (P < 0.05). The number of emetic episodes recorded on the worst day was 1.4 for the ondansetron group and 3.1 for the placebo group (P < 0.01). Patients given ondansetron had fewer days with emesis and nausea compared with placebo (P < 0.05). The mean sum score of patients weekly grading of symptoms showed that the ondansetron group had less inconvenience than the placebo group (P < 0.05). This difference persisted during the first three weeks, but not thereafter. Similarly, some quality of life measures showed significant differences in favour of the ondansetron group. More patients (n = 13) withdrew due to lack of efficacy in the placebo group compared with patients (n = 8) in the ondansetron group.

Conclusions: The present study illustrates that prophylactic anti-emetic administration of ondansetron is effective in preventing nausea and vomiting in patients undergoing fractionated radiotherapy of the abdomen.