Oral transmucosal buprenorphine provides short-term potential analgesia to domestic ferrets (Mustela putorius furo) when compared to intramuscular buprenorphine.

OBJECTIVE

To obtain pharmacokinetic data of a single dose of buprenorphine administered to ferrets via IM or oral transmucosal (OTM) routes.

METHODS

In this experimental pharmacokinetic study, domestic ferrets in a laboratory setting were randomly assigned to a treatment group of either 0.04 mg/kg of buprenorphine (0.3 mg/mL) administered IM or OTM. After a 10-day washout period, each ferret received buprenorphine via the other route of administration. Blood was collected prior to and 5, 10, 30, 60, 90, 120, 240, 360, 480, and 720 minutes following drug administration for pharmacokinetic analysis. Ferrets were excluded from the study if their vascular access buttons became nonfunctional before the end of the study. Ferrets were monitored for side effects, including increased salivation, decreased defecation, and sedation.

RESULTS

Data from 8 female domestic ferrets were used to calculate pharmacokinetic profiles. Mean maximum plasma concentration and time to maximum concentration were 5.03 ng/mL and 0.13 hours, respectively, for the IM route of administration. The mean terminal half-lives were 2.77 and 0.715 hours for IM and OTM routes of administration, respectively. Mild sedation was noted in most animals regardless of route of administration.

CONCLUSIONS

Based on effective buprenorphine plasma concentrations in dogs (0.6 ng/mL), OTM buprenorphine at a dose of 0.04 mg/kg likely provides short-term analgesia to ferrets when compared to the IM route, but administration via either OTM or IM route appears safe.

CLINICAL RELEVANCE: OTM and IM buprenorphine both reached theoretically analgesic plasma levels in ferrets, but a short half-life may limit clinical applications of the OTM route.