Antagonism of cisplatin induced emesis in the dog.

Cisplatin (cis-diammine-dichloro-platinum) administered at a dose of 3 mg/kg iv induced a reproducible and characteristic emetic response in the dog. It was characterized by a latency period (90-120 min) and multiple emetic episodes occuring within 5 hours following drug administration with sporadic delayed emesis later within the first 24 hours. There was a qualitative similarity between the emetic response of Cisplatin seen in dogs and cancer patients. Metoclopramide (1, 3 mg/kg sc) was found to be the most effective antagonsit of Cisplatin emesis in the dog while haloperidol (1 mg/kg sc) and chlorpromazine (0.3, 1, 3 mg/kg sc) offered a less complete protection. Nabilone (0.1 mg/kg iv) and AL-1612 (1 mg/kg sc) failed to to demonstrate any significant activity. A relationship between antagonism patterns of emetic responses induced by Cisplatin and apomorphine was discussed.