Naloxone

Information about Naloxone

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Naloxone-based-on-xtal-3D-bs-17

Naloxone is an opiate antagonist which is used intravenously in emergency situations to reverse the respiratory depression caused by overdoses of heroin, morphine or other opioids. {{livtox} Naloxone has not been linked to serum enzyme elevations during therapy or to clinically apparent liver injury.

Mechanism of action of Naloxone

Naloxone (nal ox’ one) is a derivative of the natural plant alkaloid thebaine and is similar to oxymorphone. Naloxone, however, is a competitive antagonist of the opiate receptors and has particularly high affinity for the μ opiate receptor and can displace morphine and other full agonists, thereby reversing their effects. Naloxone causes rapid onset of withdrawal symptoms in opioid dependent persons and is generally used in emergency rooms to treat the respiratory depression caused by opioid overdose. Naloxone has sometimes been provided to emergency medical personnel and police and fire personnel for use onsite in emergency situations.

FDA approval information for Naloxone

Naloxone was first approved for use in the United States in 1971. It remains available as a solution for injection in generic forms and under the brand name Narcan, typically in concentrations of 0.4 mg/mL to be given intramuscularly or intravenously.

Dosage and administration for Naloxone

The usual initial dose in adults with suspected opioid overdose is 0.4 to 2.0 mg. Naloxone is also available in fixed combination with buprenorphine for sublingual use (Suboxone and generic) and with pentazocine for oral use. Naloxone is poorly absorbed by the sublingual or oral route and is added to discourage the intravenous or parenteral administration of buprenorphine or pentazocine.

Side effects of Naloxone

Side effects of naloxone in opioid dependent persons include mood changes, sweating, anxiety, restlessness, trembling, dizziness, flushing, headache, nausea, vomiting, cardiac tachyarrhythmias, seizures, chest pain and acute pulmonary edema—symptoms of acute opioid withdrawal. Naloxone has minimal effects in persons not taking opioids. Naloxone is not a controlled substance, but its use is sometimes restricted to medical staff trained in emergency medicine or anesthesia. Full and partial opiod agonists:

• Alfentanil
• Butorphanol
• Codeine
• Diphenoxylate
• Fentanyl
• Heroin
• Hydrocodone
• Hydromorphone
• Levorphanol
• Loperamide
• Meperidine
• Methadone
• Morphine
• Opium
• Oxycodone
• Oxymorphone
• Pentazocine
• Remifentanil
• Sufentanil
• Tramadol

Opiate antagonists:

• Nalmefene
• Naloxegol
• Naloxone
• Naltrexone

• Dailymed label info on Naloxone
• FDA Naloxone