Opioid Antagonists

Naloxone is an opioid reversal agent that competitively blocks opioid mu receptors and reverses the effects of sedation, respiratory depression, and other effects of opioids.  Naloxone is a life-saving medication when used during opioid overdose that can be administered by a variety of routes and can be prescribed to individuals with opioid dependence who are at risk of opioid overdose.  Naltrexone is also an opioid antagonist; however, it is primarily used for treatment of alcohol use disorder and opioid use disorder after successful detoxification.

Class Drugs

• Naloxone

• Naltrexone

Class Mechanism of Action

Binds to opioid receptors

• Does not activate the receptor mediated response

Class Application

Reversal of effects of opioids

Class Adverse Effects

See individual drugs

Drug Table

Drug Name	Application	Comments	Image
Naloxone	Opioid reversal	Mechanism; -Rapid reversal of opioids; -Reverses respiratory depression and coma associated with opioid use; -Half-life is up to approximately 80 minutes, so patients can re-develop respiratory depression; Adverse Effects; -Very few adverse effects other than those intended effects of opioid reversal	"Nail" "Oxygen"
Naltrexone	Opioid Dependence; -Used after successful detoxification; Management of Alcohol Dependence; -Used in conjunction with behavioral modification program	Adverse Effects; Hepatotoxicity	"Nail" "T-Rex"