Pharmacokinetics of low-dose and high-dose buprenorphine in cats after rectal administration of different formulations.

The rectal application of buprenorphine at a dose of 0.1 mg/kg revealed a potential but weak uptake in cats. Regarding effective concentrations in previous pharmacokinetic investigations, rectal administration is currently not recommended for good provision of opioid analgesia in cats. Pharmacological investigations of formulation and galenics in order to improve the rectal bioavailability of buprenorphine remain to be clarified before further dose-finding and pharmacokinetic/pharmacodynamic studies are performed.