A randomised multicentre single blind comparison of a cannabinoid anti-emetic (levonantradol) with chlorpromazine in patients receiving their first cytotoxic chemotherapy.

One hundred and eight patients selected to receive combinations of highly emetic cytotoxic chemotherapy for malignant disease were included in a study of anti-emetic therapy. The patients were randomly allocated to receive levonantradol (0.5, 0.75 or 1 mg) or chlorpromazine (25 mg) prior to receiving their first course of cytotoxic therapy. The appropriate anti-emetic was administered 2 hr prior to the start of chemotherapy, 2 hr after chemotherapy and subsequently at 4-hourly intervals for a further 8 hr. The extent of anorexia, nausea and vomiting along with other side-effects were assessed at regular intervals by physicians and nursing staff during the 24 hr following chemotherapy. In addition, a self-assessment questionnaire was completed by the patients. Levonantradol (0.5 mg) was superior to chlorpromazine (25 mg) as an anti-emetic. Both were reasonably well tolerated, although at this dose of levonantradol 22% of patients experienced dysphoric reactions. At higher doses of levonantradol the proportion of patients experiencing these reactions rose to 50%, but without a concomitant increase in antiemetic activity. Neither drug achieved satisfactory control of vomiting in patients receiving combinations containing cis-platinum. We conclude that levonantradol (0.5 mg) is a more effective anti-emetic than chlorpromazine (25 mg) in patients receiving cytotoxic chemotherapy. However, its use cannot be recommended due to its high incidence of unacceptable central nervous system side-effects.