naloxone

noun

nal·​ox·​one na-ˈläk-ˌsōn 

: a synthetic potent antagonist of narcotic drugs (such as morphine and fentanyl) that is administered especially in the form of its hydrochloride C₁₉H₂₁NO₄·HCl

Note: Naloxone is administered by injection or as a nasal spray to reverse the effects of opioids especially in the emergency treatment of opioid overdose. It is also administered in combination with buprenorphine in the form of a dissolvable tablet placed under the tongue or a film placed inside the cheek to treat opioid dependence.

Examples of naloxone in a Sentence

Recent Examples on the Web

Experts say that even multiple high doses of naloxone might not be enough to reverse an overdose when carfentanil is involved. —ABC News, 17 Apr. 2026

Kane County residents can pick up free 988 Suicide and Crisis Lifeline yard signs, naloxone and gun cable locks at upcoming mental health events in April hosted by the Kane County Health Department. —Aurora Beacon-News, Chicago Tribune, 17 Apr. 2026

The child’s cause of death was determined to be fentanyl toxicity, and the medical examiner also found the opioid reversal medicine Narcan (naloxone) in the bloodstream, the district attorney’s office said. —Bay Area News Group, Mercury News, 16 Apr. 2026

Its strength means that the drug used to reverse opioid overdoses, naloxone, more commonly known as Narcan, may not be as effective and may require several doses to work. —Mary Walrath-Holdridge, USA Today, 8 Apr. 2026

Word History

Etymology

N-allyl + hydroxy- + -one

First Known Use

1964, in the meaning defined above

Rhymes for naloxone

• atony
• baloney
• begone
• canzone
• estrone
• fanconi
• mansoni
• moloney
• morone
• ngoni
• pallone
• quinone

Medical Definition

naloxone

noun

nal·​ox·​one nal-ˈäk-ˌsōn  ˈnal-ək-ˌsōn 

: a potent synthetic antagonist of narcotic drugs (as morphine and fentanyl) that is administered especially in the form of its hydrochloride C₁₉H₂₁NO₄·HCl

Note: Naloxone is administered by injection or as a nasal spray to reverse the effects of opioids and especially in the emergency treatment of opioid overdose. It is also administered in combination with buprenorphine in the form of a dissolvable tablet placed under the tongue or a film placed inside the cheek to treat opioid dependence. Trademarks for preparations containing naloxone include Bunavail, Evzio, Narcan, Suboxone, and Zubsolv.