Liverpool Hospital Emergency Department


  • Opiate intoxication with CNS and Respiratory depression (RR <8)
  • Can consider in Clonidine OD  


  • 400mcg/ml – ampule 
  • Infusion – 4mg Naloxone in 100ml saline 

Dosage and Administration: Caution advised with opiate dependence  

  • Bolus IV: 400mcg naloxone in 10ml syringe –with saline up to total 10ml. (40mcg/ml)
  • Provide incremental dosage increases every 2-3 minutes double dose if no response  as demonstrated below to max of 10mg
    • 40mcg (1ml) 
    • 80mcg (2ml)
    • 120mcg (3ml)
    • 160mcg (4ml)
    • 200mcg (5ml)  

If unable to obtain IV access consider: doses up to 2000mcg IM may be needed and  IN naloxone can come in a 1.8mg/ml nasal spray  

  • Infusion: start at 2/3 dose of initial dose (required in the first hour) then titrate to below end  points e.g. if 600mcg was required in the first hour, dose commence at 400mcg/hr.
  • Continue in HDU
  • Commence if multiple doses or redosing is required 

Alternative modes of delivery 

  • 400mcg IM 
  • 400mcg Intranasal 
  • 400mcg Neb  

Paediatric dosing:

  • 10mcg/kg IV bolus 

Response is indicated by:  

  • Increased RR (age appropriate) adults >8-10 when asleep and saturations >92% on  RA 
  • Improved conscious state to allow for airway protection 

Side Effects 

  • Opiate – Withdrawal 
  • Aggression/ agitation 
  • If full withdrawal – catecholamine surge – Can precipitate ACS/APO/ stroke 

Pit Falls 

  • One dose of naloxone is usually sufficient for short acting opiates e.g. heroin o Long acting opiates will likely need an infusion e.g. methadone / oxycodone / poor renal  excretion
  • Avoid in opiate dependent individuals unless signs of respiratory depression < 8 or GCS <12
  • Titrate to end point – rousable and adequate RR – avoids full reversal
  • Must observe for 2hrs post administration.
  • Larger doses of naloxone may be required for Buprenorphine or synthetic opiates