Analgesic actions of naloxone suggest the presence of a hyperalgesic opioid system.
D000700:Analgesics; D000818:Animals; D006801:Humans; D009270:Naloxone / Q000378:metabolism / Q000494:pharmacology*; D011957:Receptors, Opioid / Q000378:metabolism*
D000700:Analgesics; D011957:Receptors, Opioid; D009270:Naloxone