Nausea and vomiting in fractionated radiotherapy: a prospective on-demand trial of tropisetron rescue for non-responders to metoclopramide.

Abstract A prospective trial was performed to better assess the risk of nausea and vomiting and the rescue value of tropisetron (TRO), a 5-HT 3 receptor antagonist, in 88 patients undergoing fractionated radiotherapy to the abdomen or to large supradiaphragmatic fields and failing a first anti-emetic trial with metoclopramide (MET). Nausea was graded 0 (absent), 1 (mild), 2 (moderate) and 3 (severe). Nausea requiring anti-emetics (s grade 2) was present in 64% of the patients. MET was able to control nausea (≤ grade 1) in 26 of 58 patients (45%) who developed ≥ grade 2 nausea during radiation treatment (2 patients vomiting without nausea included). 34 patients required TRO, and 31 experienced immediate relief. However, nausea (≥ grade 2) recurred in 7 patients from 1 to 3 weeks after starting TRO. Sex, age, field type and field size (cm 2 ) did not influence the incidence and severity of nausea and vomiting. Only 24 88 patients vomited after starting radiotherapy. MET helped to eliminate emesis in one third of these patients. TRO helped to control vomiting in 73% of the salvaged patients. Constipation was observed in 8 patients on TRO and was a reason to stop the medication in 4 cases.