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Published on: July 29, 2014
Comparison of behavioral effects of morphine and fentanyl in dogs and cats
Masatoshi Kamata1, Shotaro Nagahama, Kei Kakishima
1Laboratory of Veterinary Emergency Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1–1–1 Yayoi, Bunkyo-ku, Tokyo 113–8657, Japan.
Abstract:
Behavioral effects induced by intravenous administration of morphine at 0.3, 0.6, 1.2, and 2.4 µg/kg and fentanyl at 5, 10, 20, and 40 µg/kg were evaluated in dogs and cats. In dogs, fentanyl and morphine depressed activity and level of consciousness in a dose- dependant manner. In cats, higher doses of fentanyl stimulated activity temporarily, but excitement, so-called "opioid mania," was not observed. Morphine induced distinctive behavioral changes characterized by sitting with fixed staring, and "opioid mania" was not observed in cats.
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