As part of public health initiatives, a number of countries now provide naloxone kits for use by first responders in an effort to tackle drug-related deaths within communities (Speakman et al, 2023). For those who are opioid dependent, ‘take home naloxone’ may be administered in the event of an accidental overdose, and prior to hospital admission (McAuley et al, 2023).
Naloxone hydrochloride is an opioid receptor antagonist that blocks or rapidly reverses the effects of drugs such as morphine, heroin, methadone or fentanyl. An overdose of an opioid can suppress the central nervous system, resulting in respiratory depression, bradycardia and loss of consciousness. Rapid administration of naloxone is indicated as first-line medication to reverse these symptoms which can be fatal if not treated promptly (Table 1).
Table 1. Naloxone hydrochloride for acute opioid overdose
| Acute opioid overdose–high-dose regimen to reverse potentially life-threatening effects | |||
|---|---|---|---|
| Medication | Initial dose | Secondary doses if no initial response | Post response deterioration |
| Neonate up to 28 days | Initially 100 micrograms/kg | Repeat at 1-minute intervals to a total maximum of 2 mg | Further doses may be required via intravenous route for more rapid effect |
| Child 1 month–11 years | Initially 100 micrograms/kg Maximum dose of 2 mg | Repeat at 1-minute intervals to a total maximum of 2 mg | Further doses may be required |
| Child 12–17 years | Initially 400 micrograms dose | Increase dose to 800 micrograms and repeat at 1-minute intervals for up to 2 dosesIncrease to 2 mg for 1 dose | Further doses may be required. 4 mg dose may be required in seriously poisoned patients |
| Adult | Initially 400 micrograms dose | Increase dose to 800 micrograms and repeat at 1-minute intervals for up to 2 dosesIncrease to 2 mg for 1 dose | Further doses may be required. 4 mg dose may be required in seriously poisoned patients |
Frequent monitoring of the patient's respiratory rate and level of consciousness post-naloxone administration should be undertaken as naloxone has a shorter duration of action than many opioids and repeated doses may be required (NICE, 2023a).
The prescriber must also be aware that naloxone treatment is only effective against opioids and has no impact on reversing symptoms resulting from exposure to stimulants, cocaine or benzodiazepines.
Post-recovery there is also the potential side-effect of the individual experiencing severe withdrawal symptoms (NICE, 2023b). Ongoing management should include pharmacological support of non-opioid medications to provide relief from withdrawal symptoms (Kosten and Baxter, 2019).
QUESTION 1
A 3-day-old preterm neonate is given morphine as post-operative pain relief. They become bradycardic and apnoeic. They weigh 700 g. What dose of naloxone would you prescribe?
QUESTION 2
A 10-month-old child weighing 8.7 kg was administered fentanyl. They become unresponsive with respiratory depression. What dose of naloxone would you prescribe?
QUESTION 3
An 11 year old presents with reduced consciousness, respiratory depression and bradycardia following ingestion of heroin. Their weight is estimated to be 20 kg. What dose of naloxone would you prescribe?
QUESTION 4
An adult with a known opioid dependency has taken an accidental overdose of methadone. They had been given intranasal naloxone in the community but present with ongoing respiratory depression. They weigh 60 kg. What dose of naloxone would you prescribe?