Evaluation of different doses of medetomidine for the induction of emesis in cats

Abstract

Objectives: This study aimed to investigate the emetic effect of medetomidine, determine the best dose for clinical practice and investigate any adverse effects at different doses. Methods: In this prospective, observational study, 10, 20, 30 and 40 µg/kg of medetomidine was administered intramuscularly (IM) to cats after ingestion of foreign substances, to induce emesis. The success rate, frequency, time after injection, sedation score and adverse effects were recorded. If induction of emesis was not successful after 10 or 20 µg/kg medetomidine, a second bolus of medetomidine (20 µg/kg IM) was administered 10 mins later. Results: A total of 58 cats were included after foreign material ingestion. Emesis was achieved with all doses of medetomidine (39/58), whereby the highest success rate was reached with 20 µg/kg (13/17). The success rate after the first injection was not statistically different between the different medetomidine doses (P = 0.457). The median time to emesis after the first injection of medetomidine for all cats was 5 mins (range 3–14). The sedation score was lower after 10 µg/kg medetomidine compared with 40 µg/kg (P = 0.013). The most common adverse effect was sedation. Medetomidine was antagonised with atipamezole in 47/58 cats. Conclusions and relevance: Medetomidine is an effective drug for inducing emesis in cats and is a reasonable alternative to other alpha2-agonists. The most successful dose with the least adverse effects was 20 µg/kg IM.