Naloxone

Products

Naloxone is commercially available as a solution for injection (Naloxone OrPha, Naloxone Actavis) and has been approved in many countries since 2004.

  • Information on combination with oxycodone is presented under the article Oxycodone and Naloxone (Targin, Peroral).
  • As a fixed combination with buprenorphine, naloxone is used to treat opioid dependence (Suboxone, sublingual).
  • In 2014, a naloxone auto-injector was approved in the United States (Evzio) that can be administered subcutaneously or intramuscularly by family members in an emergency.
  • A naloxone nasal spray for the treatment of opioid overdose was approved in the United States in 2015 and in many countries in 2018.

Structure and properties

Naloxone (C19H21NO4, Mr = 327.37 g/mol) is present in drugs anhydrous or as naloxone hydrochloride dihydrate, a white, crystalline, hygroscopic powder that is readily soluble in water.

Effects

Naloxone (ATC V03AB15) is a competitive opioid antagonist that abolishes opioid effects. It has the greatest affinity for the μ-receptor. Naloxone has no opioid properties and is not addictive. Effects occur rapidly after administration. The half-life is approximately 70 minutes.

Indications

  • Parenteral and nasal to reverse the effects of opioids (e.g., respiratory depression, sedation, coma, overdose, intoxication).
  • Peroral for pain management in combination with oxycodone (see there).
  • Sublingual for the treatment of opioid dependence with buprenorphine (see there).

Dosage

According to the SmPC. Unlike naltrexone, naloxone is not available orally and must be injected intravenously, intramuscularly, or subcutaneously. It is usually administered intravenously because this produces the most rapid effect.

Contraindications

  • Hypersensitivity

For complete precautions, see the drug label.

Interactions

Naloxone also cancels the desirable and undesirable effects of opioids, including pain relief, for example.

Adverse effects

The most common possible adverse effects include sweating, dizziness, lightheadedness, tremor, high blood pressure, nausea, and vomiting. Caution is advised with opioid dependence because acute withdrawal syndrome may be induced.