Potentiation of morphine analgesia by caffeine.
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.
D000698:Analgesia; D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D004357:Drug Synergism; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D002110:Caffeine; D009020:Morphine