Therapeutic action
- Specific opioid antagonist
Indications
- Respiratory depression induced by opioids(analgesia, anaesthesia, intoxication)
Forms and strengths, route of administration
- 0.4 mg in 1 ml ampoule (0.4 mg/ml) for IV, IM injection or infusion in sodium chloride0.9% or glucose 5%
Dosage
IV route is preferred, use IM route if IV route is not feasible:
- Child: 5 to 10 micrograms/kg by IV injection,repeated if necessary after 2 to 3 minutes,until adequate spontaneous ventilation is restored, followed by a continuous infusion of 1 to 5 micrograms/kg/hour, or by 5 to 10 micrograms/kg by IM injection every 90 minutes
- Adult: 1 to 3 micrograms/kg by IV injection, repeated if necessary after 2 to 3 minutes,until adequate spontaneous ventilation is restored,followed by a continuous infusion of 1 to 5 micrograms/kg/hour, or by 5 to 10 micrograms/kg by IM injection every 90 minutes
Duration
- The duration of action of naloxone (20 to 30 minutes by IV route) is shorter than that of opioids: administration must be maintained several hours even if breathing improves.
Contra-indications, adverse effects, precautions
- May cause:
- tachycardia, fibrillation, hypertension, pulmonary oedema when given postoperatively, due to a sudden reversal of analgesia;
- nausea, vomiting;
- acute withdrawal syndromein opioid-dependent patients.
- Administer with caution and reduce dosage in case of heart failure or coronary artery disease.
- Naloxone is used in addition to assisted ventilation and must be administered under close medical supervision.
- Pregnancy: risks linked to respiratory depression appear greater than risks linked to naloxone.
- Breast-feeding: no contra-indication
Remarks
Naloxone is a specific opioid antidote. It cannot be used to antagonise the effects of other drugsproducing CNS or respiratory depression.
Efficacy in antagonising opioid effects depends not only on the dose of naloxone but also on the dose and potency of the specific opioid involved.
Storage
– Below 25 °C