API

Naloxone hydrochloride

Drug classification

Opioid antagonist (competitive opioid receptor antagonist)

Dosage form

Solution For Injection

API strength per dosage

0.4 mg/ml

Dose

Adults: 0.4–2 mg IV/IM/SC; repeat every 2–3 minutes as needed, up to 10 mg. Pediatrics: 0.01 mg/kg IV/IM/SC; may increase to 0.1 mg/kg if no response. Elderly and hepatic impairment: Use with caution; titrate to response.

Mechanism of action

Competitively antagonizes μ-opioid receptors (MOR), and to a lesser extent κ-opioid (KOR) and δ-opioid (DOR) receptors, displacing opioid agonists and reversing their effects, particularly respiratory depression, sedation, and hypotension, without intrinsic agonist activity at these receptors.

Indications

Opioid overdose reversal, suspected opioid-induced respiratory depression, diagnosis of suspected acute opioid overdose, reversal of opioid effects during anesthesia, adjunct in septic shock (off-label in some guidelines).

Side effects

Nausea, vomiting, agitation, hypertension, tachycardia, sweating, tremor, headache, pulmonary edema, cardiac arrhythmia, seizures, opioid withdrawal symptoms.

Pregnancy category

Category B

Precautions

Use with caution in opioid-dependent patients, risk of acute withdrawal syndrome, monitor for recurrent respiratory depression, use cautiously in cardiovascular disease, monitor blood pressure and heart rhythm, may precipitate seizures in predisposed individuals, use in pregnancy only if clearly needed, not a substitute for emergency medical care.

Contraindications

Hypersensitivity to naloxone hydrochloride or any component of the formulation.