Ondansetron as an effective drug in prophylaxis of chemotherapy--induced emesis in children.

The chemotherapy-induced emesis causes major complications, especially in children. Traditional prophylaxis of emesis shows moderate effectiveness alongside with pronounced adverse reactions. Ondansetron, an antagonist of 5-hydroxytryptamine (subtype 3) receptor is a new, very potent drug preventing vomiting and nausea induced by different factors (chemotherapy, radiotherapy, anaesthesia). We present results of an evaluation of the activity of ondansetron in 35 children receiving highly emetogenic chemotherapy during 129 days (102 with no cisplatin and 27 with cisplatin). On these days Zofran was administered as a single antiemetic agent. On 85 days the dosage was lower than recommended (the lowest 2 mg/m2/day). 16 out of the 35 patients received during 85 days traditional antiemetic treatment, and they constitute the control group. In chemotherapy without cisplatin complete and major responses were observed in 85.3% of the patients, in chemotherapy including cisplatin the respective response rate amounted to 71.4% while with, the traditional antiemetics the response rate was 38.8%. The dose reduction does not seem to have negatively affected the results, since they are comparable with those reported in the literature. Similar favourable effects were achieved in 8 children in which Zofran was used during the conditioning for bone marrow transplantation. This is of special significance in children conditioned with busulfan. This agent may be given only orally, and the effectiveness of the treatment depends directly on the dose of the administered drug. No adverse effects linked to ondansetron were found. The patients reaction was very positive, as ondansetron causes no sedation. Ondansetron seems, therefore, to be an effective and safe antiemetic.