Thermal antinociception after dexmedetomidine administration in cats: A comparison between intramuscular and oral transmucosal administration

Abstract

Dexmedetomidine 40 μg/kg was administered either intramuscularly (IM) or oral transmucosally (OTM) to 12 cats in a randomised cross-over study. Thermal nociceptive thresholds and visual analogue scale (VAS) sedation scores were obtained before and at regular intervals up to 24 h after test drug administration.

The summary measures of overall mean threshold, overall mean VAS sedation plus onset, offset and duration of analgesia were investigated using a univariate general linear model. There were no significant differences between treatment groups. Data are presented as mean±standard deviation: delta T mean increase over time (IM 6°C±3°C, OTM 6°C±2°C); overall mean VAS (IM 43±9 OTM 39±1); onset (IM 35±32 and OTM 30±40 min); offset (IM 96±56 and OTM 138±135 min); duration (IM 61±47 OTM 99±124 min). Dexmedetomidine is well absorbed through the oral mucosa in cats since OTM and IM administration of dexmedetomidine 40 μg/kg produced similar overall sedative and antinociceptive effects.