naloxone hydrochloride: clinical use

Prescribing considerations

• Titrate the clinical response to restore adequate ventilation while avoiding unnecessary loss of analgesia or abrupt withdrawal.
• Consider whether the opioid’s duration may exceed naloxone’s effect and arrange sustained observation and respiratory support.
• An incomplete response should prompt consideration of non-opioid causes, mixed poisoning or buprenorphine exposure.
• Use particular caution after high opioid exposure, in physical dependence and after surgery.

Contraindications and cautions

• Hypersensitivity to naloxone hydrochloride or any excipient.
• Use caution in cardiovascular disease or with substances and medicines associated with serious cardiac effects.
• Rapid reversal in opioid-dependent patients, including affected newborns, may precipitate severe withdrawal.

Monitoring

• Airway, respiratory rate, oxygenation and need for ventilatory support
• Consciousness and recurrence of opioid toxicity
• Pulse, blood pressure and cardiac rhythm where clinically indicated
• Acute withdrawal, vomiting, pulmonary oedema and return of pain

Clinical pharmacology

Naloxone is a competitive opioid-receptor antagonist with high receptor affinity. It is rapidly distributed, mainly metabolised by hepatic glucuronidation and has a shorter effect than some opioids, permitting recurrent toxicity.

Formulation and product differences

• The selected product is a clear, colourless solution for intravenous or intramuscular injection or intravenous infusion.
• It is supplied in single-use glass ampoules that should be protected from light.
• Before use, inspect the solution and discard it if discoloured or visibly particulate.
• For infusion, use only compatible diluents and avoid alkaline solutions or preparations containing bisulphite, metabisulphite or high-molecular-weight anions.

Injection

Route: Parenteral

Strengths: 400 micrograms/mL, 1 mg/mL