%0 Journal Article %T Naloxone (narcan) %D 1975 %R 10.1136/dtb.13.19.75 %J Drug and Therapeutics Bulletin %P 75-76 %V 13 %N 19 %X Naloxone (Narcan - Winthrop), the N-allyl derivative of oxymorphone, is a narcotic antagonist whose most important clinical property is reversal of narcotic-induced respiratory depression. Like nalorphine (Lethidrone - Wellcome) and levallorphan (Lorfan - Roche), it also antagonises the sedative, analgesic and miotic effects of narcotic analgesics.1 There is, however, an important difference. When not preceded by the administration of a narcotic or when given in excess, nalorphine and levallorphan themselves have narcotic effects; by contrast, naloxone has none.2 It is, for all practical purposes, a pure antagonist, whereas nalorphine and levallorphan are partial agonists, with agonist as well as antagonist effects.3 %U https://dtb.bmj.com/content/dtb/13/19/75.full.pdf