Reduced consciousness with a respiratory rate of 8 or less and pinpoint pupils: support ventilation and give naloxone. The triad is coma, pinpoint pupils and respiratory depression. Re-sedation is common because naloxone is short-acting.
Naloxone
- 400 micrograms IM or IV, repeat every 2 to 3 min titrated to breathing
- Larger or repeated doses for potent synthetic opioids (for example fentanyl)
- Set up an infusion if repeated boluses are needed
- IM is useful if IV access is difficult
After reversal
- Observe for re-sedation: often at least 6 h, and longer (for example 12 h or more) for long-acting opioids such as methadone
- Expect acute withdrawal (agitation, vomiting) if over-reversed
- Beware co-ingestants (benzodiazepines, alcohol, stimulants)
Drowsy, protecting airway
- Reduced RR, pinpoint pupils
- Observe closely, oxygen
- Prepare naloxone
Respiratory depression
- RR under 8 to 10, hypoxia
- Naloxone 400 micrograms, titrate
- Repeat every 2 to 3 min
Arrest / deep coma
- Apnoea or arrest
- High-dose naloxone, ventilate, ALS
- Naloxone infusion (short half-life)
Care bundle
1
1. Airway and breathing
Open the airway and support ventilation with bag-mask and oxygen; this is the priority alongside naloxone.
Open the airway and support ventilation with bag-mask and oxygen; this is the priority alongside naloxone.
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2
2. Naloxone
Titrate to adequate breathing, not full alertness, to avoid a combative acute withdrawal. Reassess continually.
Titrate to adequate breathing, not full alertness, to avoid a combative acute withdrawal. Reassess continually.
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3
3. Harm reduction
Offer a take-home naloxone kit and training, and advise never to use alone. Treat injection-site complications.
Offer a take-home naloxone kit and training, and advise never to use alone. Treat injection-site complications.
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4
4. Refer and follow up
Refer to substance misuse services and address social needs. Do not discharge early if a long-acting opioid is involved.
Refer to substance misuse services and address social needs. Do not discharge early if a long-acting opioid is involved.
Remember
- Naloxone wears off before many opioids: watch for relapse into respiratory depression
- A patient who self-discharges after naloxone is at risk of dying from re-sedation
- Consider other causes of a reduced GCS
Pitfalls
- Giving naloxone without supporting ventilation
- Over-reversing and precipitating severe withdrawal
- Discharging too early after a long-acting opioid
- Missing co-ingestants
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026