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Naloxone and managing opioid complications (Guidelines)



  • Argyll & Bute HSCP and Highland HSCP
  • Secondary Care.

Naloxone must be readily available on all wards where opioids are used.

All trained nursing staff should know where it is stored.

Is patient’s respiratory rate 7 and a sedation score of 2?

Is the patient’s sedation score 3?


  1. Prepare solution in a 5mL syringe using 3mL of 9% sodium chloride and 400 micrograms (1mL) NALOXONE, checking expiry date of both drug and diluent.
  2. Administer the Naloxone intravenously in 100mcg increments every minute, until the respiratory rate if greater than 10 and the patient’s sedation score is 0 or 1.
  3. Maximum dose of Naloxone should be 400 micrograms. If this dose has not given adequate response then consider other causes of respiratory depression. 
  4. Naloxone has a shorter duration of action than most opioids so patients requiring it need to be monitored for an extended period to ensure the antidote does not wear off before the effect of the opioids.
  5. Therefore patients may also need repeated doses or an infusion. See A&E infusion guideline (see resources).
  6. OTHER CAUSES SHOULD BE CONSIDERED. Please ask for surgical review
  7. Monitor respiration rate, sedation score and oxygen saturations every 15 minutes for 1 hour and hourly for 4 hours thereafter, to ensure respiratory depression does not return. Pulse oximetry should be used continuously until opioids are no longer required.
  8. Contact the Acute Pain Nurse or ITU Anaesthetist to reassess the patient’s analgesia requirements and whether a naloxone infusion is required.

Management complications of opioids

NSAIDs and Paracetamol help to minimise opioid side-effects by reducing the total dose of opioid required and should be prescribed regularly not PRN.

Moderate respiratory depression: respiratory rate less then 9 breaths per minute and sedation score of 1 or 2.

  • Ensure a clear airway and administer Oxygen therapy 10 L/minute via facemask.
  • Monitor respiratory rate, sedation score and oxygen saturation every 15 minutes until respiratory rate is 10 per minute or more.
  • Review the analgesia and consider other causes of respiratory depression.
  • Contact the Acute Pain Team for further advice.

Severe respiratory depression: respiratory rate less then 7 breaths per minute OR sedation score of 3.


  • Contact the Ward FY1, Surgical Registrar or Nurse Practitioner. Stop morphine pump.
  • Give NALOXONE 100 micrograms intravenously. Repeat after 1 minute until there is an adequate response. Max 400 microgram.
  • Review analgesia, consider and exclude any other causes of respiratory depression: hypovolaemia, anaphylaxis or cardiac problems.
  • A sedation score of 3 is unusual when PCA is used correctly: it may be associated with someone other than the patient pressing the PCA button.
  • Contact the Acute Pain Nurse or ITU Anaesthetist to reassess analgesic requirements and whether a naloxone infusion is required.

Last reviewed: 31/10/2022

Next review date: 31/10/2025

Author(s): Acute Pain Team.

Version: 2

Approved By: TAMSG of the ADTC

Reviewer name(s): Louise Reid, Clinical Nurse Specialist, Claire Wright Acute Pain Nurse Specialist L.

Document Id: TAM108

Internal URL:

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Self-management information