Randomized crossover antiemetic study in cisplatin-treated patients. Comparison between high-dose i.v. metoclopramide and high-dose i.v. dexamethasone.

This prospective, randomized, nonblind study comparing the antiemetic effectiveness of high-dose IV metoclopramide and high-dose IV dexamethasone was performed in 78 advanced cancer patients. Chemotherapeutic treatment consisted in cisplatin at a high-dose (120 mg/m2) (HD-CDDP) and at a low-dose (LD-CDDP), either alone (60 mg/m2) or in combination with other chemotherapeutic agents (50 mg/m2). The evaluation of the effectiveness of antiemetic therapy was based on three parameters: prevention of vomiting ("major protection"), number of emetic episodes, and subjective preference. Out of 78 study patients, 67 were evaluable. Overall, metoclopramide proved to be statistically superior to dexamethasone in preventing vomiting (P less than 0.005), in reducing the median/mean number of emetic episodes (P less than 0.001/0.001), and in subjective preference (P less than 0.01). The results divided between HD-CDDP and LD-CDDP groups were also in favor of metoclopramide for reduction of the median/mean number of emetic episodes (P less than 0.001/0.001 for the HD-CDDP group and P less than 0.001/0.005 for the LD-CDDP group) and in subjective preference (P less than 0.001 and P less than 0.001 for the HD- and LD-CDDP groups, respectively). No statistical differences were noted when LD-CDDP was used in monochemotherapy, whereas when LD-CDDP was used in combination chemotherapy, statistical differences in favor of metoclopramide were noted again for the median/mean number of emetic episodes (P less than 0.01/0.05) and for subjective preference (P less than 0.01), even though the effectiveness of both antiemetic agents was greatly reduced. The evaluation of previously untreated patients reflected the overall results: for the HD-CDDP group all three parameters demonstrated statistical significance in favor of metoclopramide; for the LD-CDDP group, of all three parameters, prevention of vomiting (major protection) was the only one for which there was no significant difference. Mild sedation was the only side effect of metoclopramide. No extrapyramidal reactions were noted during this trial, but concomitant orphenadrine treatment was given. Dexamethasone was always well tolerated. In conclusion, high-dose IV metoclopramide demonstrated its superiority over high-dose IV dexamethasone in all subsets of our population except the LD-CDDP monochemotherapy group, in which the two antiemetics were found to be equivalent in effect.