What is the recommended treatment for a suspected opioid overdose in an adult with a history of opioid use?

Naloxone for Suspected Opioid Overdose

For an adult with suspected opioid overdose who has a pulse but no normal breathing or only gasping, immediately open the airway and provide rescue breathing or bag-mask ventilation, then administer naloxone 0.4-2 mg intramuscularly or intranasally while continuing standard BLS care. 1

Immediate Management Algorithm

Step 1: Airway and Breathing (Highest Priority)

• Open the airway and provide bag-mask ventilation BEFORE naloxone administration 2, 3
• This takes absolute precedence over pharmacologic intervention because opioid overdoses progress to cardiac arrest through loss of airway patency and respiratory failure 1, 3
• Maintain rescue breathing at 1 breath every 5-6 seconds (10-12 breaths/minute) until spontaneous breathing returns 1
• Activate emergency services immediately—do not delay while awaiting naloxone response 1

Step 2: Assess Patient Status

If pulse present but no normal breathing or only gasping (respiratory arrest):

• Administer naloxone while continuing ventilation 1
• Initial dose: 0.4-2 mg IV, or 2 mg IM/intranasal if IV access unavailable 1, 4
• Repeat every 2-3 minutes until respiratory rate ≥10 breaths/minute 2, 4

If no pulse (cardiac arrest):

• Standard CPR takes absolute priority over naloxone 1
• Focus on high-quality chest compressions and ventilation—naloxone has no proven benefit in cardiac arrest 1
• Naloxone may be considered after CPR initiation only if high suspicion for opioid overdose and does not delay compressions 1

Naloxone Dosing by Route

Intravenous (Preferred if access available)

• Initial: 0.4-2 mg IV 1, 4
• For opioid-dependent patients: Start with 0.04-0.4 mg to minimize withdrawal 4, 5
• Repeat every 2-3 minutes if inadequate response 2, 4

Intramuscular/Intranasal (If IV unavailable)

• 2 mg IM or intranasal 1, 4
• Repeat in 3-5 minutes if necessary 2, 4
• Higher-concentration intranasal naloxone (2 mg/mL) has efficacy similar to intramuscular with response time averaging 3.4 minutes 6, 7

Critical Dosing Principle

• Titrate to eliminate respiratory depression, NOT to full consciousness 2, 4
• Goal: Restore respiratory rate to normal while minimizing withdrawal symptoms 2, 8
• Excessive doses cause hypertension, tachycardia, agitation, vomiting, and circulatory stress 4, 5

Post-Administration Monitoring Requirements

Mandatory Observation Period

• All patients must be observed in a healthcare setting until risk of recurrent toxicity is low and vital signs normalized 1, 3
• Minimum 2 hours after discontinuation of naloxone 3
• Longer observation for long-acting opioids (methadone, sustained-release formulations) 4, 3
• Naloxone duration of action (30-70 minutes) is often shorter than opioid effects 1, 4, 3

Continuous Naloxone Infusion (If repeated boluses required)

• Prepare 2 mg naloxone in 500 mL normal saline (concentration 0.004 mg/mL) 2, 4
• Standard protocol: Two 0.4 mg ampoules diluted in 250 mL over 3-4 hours, repeat as necessary 2
• Consider ICU transfer for patients requiring mechanical ventilation or continuous infusion 2

Monitor Specifically For:

• Respiratory rate and effort 2, 3
• Level of consciousness 2, 3
• Blood pressure and heart rate 2
• Oxygen saturation 2

Critical Pitfalls to Avoid

Never discharge after initial response: Recurrent respiratory depression is common even when patients appear fully recovered 2, 4, 3

Never delay ventilation waiting for naloxone: Bag-mask ventilation must begin immediately while naloxone is being prepared 2, 3

Never assume opioid-only overdose: Naloxone is ineffective for benzodiazepines and other non-opioid drugs—maintain full resuscitative support regardless 1, 4

Never use excessive doses in opioid-dependent patients: Start with lower doses (0.04-0.4 mg) to avoid precipitating severe withdrawal syndrome 4, 5

Special Considerations

Opioid-Dependent Patients

• Use challenge dose of 0.1 mg/70 kg initially if dependency suspected 8
• If no withdrawal in 2 minutes, proceed with standard dosing 8
• Lower initial doses minimize withdrawal while maintaining efficacy 4, 5

Alternative Routes When IV Access Lost

• Intramuscular or subcutaneous 1 mg dose effective within 5-15 minutes 8
• Intranasal administration via mucosal atomizer device shows 91% response rate 6
• Nebulized naloxone (2 mg) shows 81% complete or partial response in patients with spontaneous respirations 9

Renal or Hepatic Impairment

• Standard dosing applies for single episodes 8
• Deliver incremental doses slowly (over 60 seconds) to minimize hypertension and dizziness 8