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Naloxone Hydrochloride Injection, USP

Pfizer · FDA-approved active Small molecule

Naloxone competitively blocks opioid receptors to rapidly reverse opioid overdose and restore normal breathing.

Naloxone competitively blocks opioid receptors in the central nervous system, rapidly reversing the effects of opioid overdose. Used for Reversal of opioid overdose and opioid-induced respiratory depression, Emergency treatment of known or suspected opioid poisoning.

At a glance

Generic nameNaloxone Hydrochloride Injection, USP
SponsorPfizer
Drug classOpioid antagonist
TargetOpioid receptors (mu, delta, kappa)
ModalitySmall molecule
Therapeutic areaEmergency Medicine / Toxicology
PhaseFDA-approved

Mechanism of action

Naloxone is a non-selective opioid antagonist that binds with high affinity to mu, delta, and kappa opioid receptors, displacing opioid agonists and preventing their effects. By blocking opioid receptor activation, it reverses respiratory depression, sedation, and other life-threatening effects of opioid overdose. Its rapid onset and short duration make it ideal for emergency reversal of acute opioid toxicity.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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