Analgesic Efficacy and Safety of Buprenorphine in Chinchillas (Chinchilla lanigera)

Abstract

Buprenorphine is routinely used in chinchillas at reported doses of 0.01 to 0.1 mg/kg IM or SC. However, these dose recommendations are based on anecdotal reports or extrapolation from studies in other species. Therefore, the purpose of this study was to evaluate the analgesic efficacy and safety of subcutaneously administered buprenorphine in chinchillas. Using a randomized, blind, controlled, complete crossover design, we evaluated buprenorphine at a single dose of 0.05, 0.1 or 0.2 mg/kg SC (experiment A) and 0.2 mg/kg SC (experiment B). Analgesic efficacy was determined by measuring limb withdrawal latencies in response to a thermal noxious stimulus (Hargreaves method) at 0, 3, 6, 12, and 24 h (experiment A) and at 0, 1, 2, 4, and 8 h (experiment B). In a third experiment, food intake and fecal output were monitored after repeated administration of buprenorphine (0.2 mg/kg SC every 6 h for 3 doses). Buprenorphine at 0.2 mg/kg SC, but not at 0.05 or 0.1 mg/kg SC, significantly increased limb withdrawal latencies for less than 4 h. Self-limiting reduction in food intake and fecal output occurred after administration at the 0.2-mg/kg dose in animals undergoing algesiometry. In chinchillas not undergoing algesiometry, the administration of 3 doses at 0.2 mg/kg SC every 6 h did not reduce food intake but significantly decreased fecal output for the first 24 h. Additional studies are needed to evaluate buprenorphine in different algesiometry models and to establish its pharmacokinetic profile in chinchillas.

Carboplatin‐induced myelosuppression as related to body weight in dogs

“…Since carboplatin is excreted by glomerular filtration and active renal tubular transport, decreased renal function can lead to increased myelosuppression from carboplatin. 35 For this reason, dose reductions for carboplatin are routinely recommended in people with decreased creatinine clearance. 1 Measurement of glomerular filtration rate (GFR) by creatinine clearance or nuclear scintigraphy is used in humans to determine a more accurate picture of renal function and used to calculate the carboplatin dose.…”

Intramuscular alfaxalone with or without buprenorphine or hydromorphone provides sedation with minimal adverse effects in healthy rabbits (Oryctolagus cuniculus) in a randomized blinded controlled trial

“…31 In chinchillas, 0.2 mg of buprenorphine/kg SC, but not 0.05 to 0.1 mg/kg, significantly increased limb withdrawal latencies in response to a thermal noxious stimulus. 33 Although studies evaluating antinociceptive effects of opioids in rabbits are lacking, on the basis of results of this study, IM administration of hydromorphone may be a better choice for rabbits undergoing painful procedures. Studies evaluating higher doses of IM administration of buprenorphine and antinociception are required.…”

Pharmacokinetic and safety assessment of carboplatin‐impregnated calcium sulfate hemihydrate beads in eight rats

“…The maximally tolerated doses reported and used in the clinical setting (60 mg/m 2 cisplatin [dogs], 300 mg/m 2 carboplatin [dogs], and 200 mg/m 2 carboplatin [cats]) were not exceeded in any of the prior studies. 2,20,21,23,[43][44][45] The dose used in the current study would be below the maximally tolerated dose, and dosing levels for specific tumor types ideally should be established prior to clinical use. 20 Clinically, the amount of carboplatin implanted using CI-CSH beads, will likely not provide IV concentrations that will exceed any IV administration limits, based on the data obtained in cats.…”