Intra and postoperative effectives of oral transmucosal administration of phenylbutazone for pain managament in dogs

The aim of the present study was to evaluate the efficacy and analgesic duration of single dose of phenylbutazone administered by oral transmukosal route immediately before induction of anesthesia in dogs undergoing elective ovariohysterectomy. Eight-teen sexually intact female dogs (weiging between 5 and 30 kg, and 1 to 7 yrs of age) referred for ovariohysterectomy procedure from a local shelter at regular intervals over 3 months were included in the study. The dogs were administered phenylbutazone on the basis of their respective treatment group (20 mg/kg via oral transmucosal administration) immediately before anesthetic induction. The syringe was placed in the cheek pouch of the dog, and phenylbutazone was slowly administered over a period of 1 to 3 minutes to ensure the drug did not drip out of the dog's mouth, or was not swallowed by the dog. In control group, 0.9% NaCl was administered in the cheek pouch of the dog. Throughout the study, pre and postoperative pain was assessed at baseline (before induction of anesthesia) and then at 0.5, 1, 2, 3, 8, and 24 hrs after the surgery. Group oral transmucosal had significantly lower Glascow pain scores than the control group at the 0.5, 1, 2, 3, and 8 hour postoperative periods. In conclusion, a single dose of phenylbutazone administered via the oral transmucosal route before surgery may be particularly beneficial for acheiving reasonable perioperative analgesia, but not in postoperative period.