Action of glucocorticoids to antagonise cisplatin-induced acute and delayed emesis in the ferret.

Cisplatin 5 mg/kg, i.p. induced an acute (day 1) and delayed (days 2 and 3) emetic response in the ferret that was used to investigate the potential anti-emetic activity of several glucocorticoids. Betamethasone (0.3-3 mg/kg, i.p.) reduced the emesis occurring during the initial 0-24-h period by 71.1-99.5% (P<0.05). The action of methylprednisolone (1.0-10.0 mg/kg, i.p.) and hydrocortisone (1.0-30.0 mg/kg, i.p.) could not be assessed because the controls exhibited weak emetic responses and dexamethasone produced a non-significant 64.0% reduction at 0.3 mg/kg (P>0.05). However, all glucocorticoids dose-dependently reduced retching+vomiting during the subsequent 24-56-h period. The rank order of anti-emetic potency was betamethasone (ID(80)<0.3 mg/kg)>/=dexamethasone (ID(80)=0.32 mg/kg)>methylprednisolone (ID(80)=0.66 mg/kg)&z.Gt;hydrocortisone (ID(80)>30 mg/kg). Dexamethasone was ineffective to antagonise the retching+vomiting response during the 24-56-h period when the administration was delayed until 24 h post-cisplatin injection. None of the glucocorticoids reduced the retching+vomiting response occurring during the 56-72-h period. In conclusion, the rank order of anti-emetic potency suggests that inflammation, or mediators of inflammation, contribute to the retching+vomiting response induced by cisplatin.