Tropisetron, a new 5-HT3 receptor antagonist, in the prevention of irradiation-induced nausea, vomiting and diarrhoea.

Tropisetron, a 5-HT3 receptor antagonist, was evaluated as antiemetic prophylaxis during postoperative abdominal irradiation of ovarian carcinoma patients. Twenty consecutive women with Stages I-III (FIGO) epithelial ovarian carcinomas were included. At the start of radiotherapy all patients were clinically tumor-free. Twelve women received irradiation on whole-abdominal fields, 1.0 Gy per fraction, during 6 weeks. Eight women were irradiated on the lower abdomino-pelvic fields, 1.7 Gy per fraction, during 5 weeks. Efficacy and adverse events were recorded by the patients in diary-form booklets using visual analog scales (VAS). All patients completed the treatment series and none was lost to follow-up. Nausea, generally mild (mean 20 mm VAS) and of short duration, increased from start (30%) to end of radiotherapy (54%). Episodes of vomiting were few in number and occurred in less than 10% of the cases. Diarrhoea was common towards the end of the radiotherapy courses, especially when the dose per fraction was 1.7 Gy and the need for extra antidiarrhoeal medication (loperamide) increased from 38% at the start to 100% at the end. The mean weight loss was only 1.2 kg during 5-6 weeks. The overall ratings for quality of life were excellent or good in 75-85% of the cases. The efficacy of tropisetron was rated excellent or good in 80% of the cases and the tolerability likewise in 85% in the overall evaluation of the drug made by the investigator. Tropisetron therefore seems to be a promising and well-tolerated drug in conjunction with extended radiotherapy on the whole- or lower-abdominal fields.(ABSTRACT TRUNCATED AT 250 WORDS)