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Updated: Oct 7, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
Potentiation of morphine analgesia by caffeine
Abstract:
Significant potentiation of morphine (5 mg kg-1 s.c. or 1 mg kg-1 i.v.) analgesia (tail-withdrawal reflex at 55 degrees C) was observed in caffeine-treated (100 mg kg-1 i.p.) rats as compared to the control group and lower doses of caffeine (2mg kg-1 i.p.) did not show this effect. Potentiated analgesia was reversed by naloxone. Pharmacokinetic or dispositional factors appear to be involved in part in this potentiation.
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