from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A drug, C19H21NO4, used in its hydrochloride form as an antagonist to narcotic drugs, such as morphine.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A drug used to counter the effects of an overdose on opioids (such as heroin or morphine).

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a potent narcotic antagonist (trade name Narcan) especially effective with morphine


from The American Heritage® Dictionary of the English Language, 4th Edition

[n(ormal) + al(lyl) + (hydr)ox(y) + (morphin)one, compound related to morphine.]


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  • Treatment with naloxone is controversial and has been reported to cause hypertension. 3-5 However, transient hypertension can be seen from clonidine alone.

    Clonidine Overdose in Children

  • It's called naloxone -- and I've written about it previously here and here.

    Maia Szalavitz: AP Thinks Heroin's Got a Brand New Bag, Misses Story

  • Victims can be revived without lasting effects if the antidote -- a drug called naloxone (brand: Narcan) -- is given early enough.

    Maia Szalavitz: How Not to Die Like Heath Ledger, Part II

  • The nasal spray is a drug called naloxone, or Narcan.

    Mark Kleiman: Killing in the name of public health

  • They then switched to another antidote called naloxone, and that is an antidote that is specifically used to treat drug overdose, specifically heroin or other opiates, and that apparently, according to reports received by U.S. officials, did work with many of the victims.

    CNN Transcript Oct 28, 2002

  • The budget also ignores life-saving harm reduction measures such as naloxone-distribution and heroin assisted treatment, widely viewed around the world as a necessary part of any balanced, evidenced based drug strategy.


  • Further, the current therapy to overcome the respiratory depression of administering μ-opiate receptor antagonists, such as naloxone, has the distinctly undesirable effect of removing analgesia.

    PLoS ONE Alerts: New Articles

  • * Opioid antagonists such as naloxone and nelmefene


  • * Opioid antagonists such as naloxone and nelmefene


  • Solutions to the crisis exist; cost-neutral and cost-effective measures such as Good Samaritan 911 laws and expanded access to the lifesaving overdose reversal medication naloxone help reduce overdose deaths.

    Amy Winehouse: Reflections from Two Drug Policy Activists


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  • Wowee, I wasn't aware of the medical meaning of antagonist that WordNet uses.

    February 17, 2009