Ondansetron versus metoclopramide as antiemetic treatment during cisplatin-based chemotherapy. A prospective study with special regard to regard to electrolyte imbalance.

Cancer patients selected for cisplatin-based chemotherapy were randomly divided into two groups (42 patients in each) which received either metoclopramide or ondansetron as antiemetics. Metoclopramide was given i.v. with 5 doses of 2 mg/kg starting 30 min before the cisplatin infusion and continued with one dose every 3 h. Ondansetron was given with a first injection of 8 mg i.v. 30 min before the cisplatin infusion; the patients were given 8 mg orally 5 and 10 h after the cisplatin infusion followed by 8 mg x 3 during the next two days. In the present study ondansetron was superior to metoclopramide concerning antiemetic efficacy and gave also less side-effects as diarrhea, dizziness, extrapyramidal symptoms and electrolyte imbalance (sodium, potassium, magnesium, phosphorous) during the first 24 h following the cisplatin infusion.