Sublingual administration of detomidine in horses: sedative effect, analgesia and detection time.
A single dose of 40 μg/kg bodyweight (BW) of oromucosal detomidine gel was administered sublingually to 10 healthy Dutch Warmblood mares aged 7 ± 4 years (mean ± SD) and BW 580 ± 69 kg. Blood and urine samples were collected before and for 8 days following administration and evaluated qualitatively in an FEI Reference Laboratory and quantitatively in a research laboratory. Clinical effects were evaluated at baseline and for 24 h after administration. Sedation was determined using head height and scores of reaction to auditory and mixed auditory/sensory stimuli. Mechanical nociceptive thresholds (MNTs) were assessed using pressure algometry to evaluate analgesia. Heart rate (HR) was measured and ataxia scored. All horses were considered negative for detomidine in blood samples by 48 h post-administration and in urine by 60 h. These results indicated that a safe withdrawal time for detomidine oromucosal gel may be 72 h following a single sublingual administration of 40 μg/kgBW. Decreases in HR and head height were maximal at 40 and 60 min post-administration, respectively. The maximal decrease in response to stimuli was observed at 100 min. Ataxia was maximal at 60 min. At 40 and 80 min MNTs were significantly increased compared to baseline. All parameters, except the MNTs of two locations, which were decreased, returned to baseline values within 24 h post-administration.
Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 114, 3584 CM Utrecht, The Netherlands. j.j.lami@uu.nl
Jiske J
JJ
L'Ami
Lian E
LE
Vermunt
Johannes P A M
JP
van Loon
Marianne M
MM
Sloet van Oldruitenborgh-Oosterbaan
D000286:Administration, Sublingual; D000818:Animals; D001259:Ataxia / Q000139:chemically induced; D001522:Behavior, Animal / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006736:Horses; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology*; D007093:Imidazoles / Q000008:administration & dosage / Q000494:pharmacology*; D010146:Pain / Q000517:prevention & control / Q000662:veterinary*
D006993:Hypnotics and Sedatives; D007093:Imidazoles; C041255:detomidine