A comparison of the sedative and analgesic properties of pethidine (meperidine) and butorphanol in dogs

O bjectives : To compare the analgesic and sedative effects of butorphanol and pethidine (meperidine) in dogs.M ethods : Twenty‐eight female dogs undergoing ovariectomy (20) or ovariohysterectomy (8) were randomly divided into two groups. Pre‐anaesthetic medication in group B consisted of 20 μg/kg intramuscular (im) acepromazine and 0·4 mg/kg butorphanol, while group P received 20 μg/kg acepromazine with 5 mg/kg pethidine. The resulting sedation (simple descriptive scale), propofol dose required to induce anaesthesia, several intraoperative cardiorespiratory variables and postoperative pain (Colorado Pain Scoring System) were compared between the two groups. A 0·2 mg/kg meloxicam dose was administered intravenously to all animals at the end of the 4 hours observation period, or earlier if the pain score was more than 13.R esults : Sedation scores, propofol induction doses and intraoperative cardiorespiratory variables were not different between groups. Postoperative pain scores were also similar although one dog in group B required rescue analgesia. Five dogs in group P vomited postoperatively.C linical S ignificance : Either butorphanol and pethidine, combined with acepromazine, produced reliable sedation and analgesia up to 4 hours after intramuscular injection in dogs.