Effects of Ondansetron on Xylazine Induced Emesis in Cats

Objective- Vomiting frequently is reported after xylazine administration in cats. This study evaluates prophylactic antiemetic efficacy of ondansetron in cats sedated with xylazine HCl. Design- Experimental study. Animals- Six healthy adult cats from both genders were selected for the study. Interventions- Intramuscular injection of normal saline was administered an hour before intramuscular injection of xylazine (0.66 mg/kg) on day 0 (control treatment). Ondansetron was injected in three increasing dosages (0.2, 0.4 and 0.8 mg/kg) an hour prior to administration of xylazine on days 7, 14 and 21, respectively (experimental treatments). All the cats were fed with commercial food after ondansetron or saline injection. Measurements and Main Results- They were monitored after injection of xylazine for thirty minutes to record the onset of first emetic response, frequency of emetic episodes and the onset of recumbency. All data were analyzed using Wilcoxon signed-rank test. Prior treatment with each dosage of ondansetron significantly reduced the frequency of emetic episodes (p<0.05). Ondansetron administration prior to xylazine injection didn’t increase the time until onset of the first emetic episode and also onset of recumbency at any of mentioned dosages. Conclusions and Clinical Relevance- Ondansetron may be used as a prophylactic antiemetic in cats sedated with xylazine HCl.