The prophylactic anti-emetic effect of five dosages of metoclopramide (0.2, 0.4, 0.6, 0.8 and 1 mg/kg, IM) was evaluated against saline solution, both injected 1 h before administration of xylazine in cats. Saline was administered to cats (day 0) followed by sequentially increasing dosages of metoclopramide at 1-week intervals. After xylazine injection, all cats were carefully observed to record the frequency of emesis and the time until onset of the first emetic episode. The onset of sedation in these cats was also studied. Prior treatment with each dosage of metoclopramide significantly reduced the frequency of emetic episodes (P<0.05). Metoclopramide administration prior to xylazine injection did not alter the time until onset of the first emetic episode at any of mentioned dosages, but significantly reduced the time until onset of sedation only at the dose of 1 mg/kg. Metoclopramide may be used as a prophylactic anti-emetic in cats sedated with xylazine hydrochloride.