Comparison of antiemetic activity of chloropromazine and high doses of metoclopramide in cisplatin-based chemotherapy.

High dose metoclopramide and different phenothiazines are widely used antiemetics in cancer patients receiving chemotherapy. In a prospective randomized study we compared the antiemetic efficacy of high dose metoclopramide (M) and chloropromazine (C). We also tested the role of dexamethasone (D) when combined with either of these drugs. A total of 165 patients were randomly allocated to 5 groups with 33 patients in each group. Group A received only M, group B: M + D, group C: C + D, group D: M + D + C and group E: M + C. All patients received combination chemotherapy with cisplatin for the first time and were evaluated only once in order to exclude anticipatory nausea and vomiting. Patients in group C had less antiemetic protection than the other groups (p less than 0.001). Groups A, B, D, E, had more or less equal antiemetic efficacy, although the efficacy in group B was somewhat better; this difference was not statistically significant. Side-effects were minimal. Chloropromazine seemed to protect patients who received metoclopramide from extrapyramidal manifestations. In conclusion the results suggest that high dose metoclopramide has a better antiemetic effect than chloropromazine, dexamethasone is a helpful adjuvant drug when used in combination with an effective antiemetic agent, and chloropromazine and dexamethasone may prevent the extrapyramidal side-effects that can occur when metoclopramide is used as single antiemetic drug.