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Opioid Overdose

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Overview

Opioid Overdose

Quick Reference

Critical Alerts

  • Airway and ventilation first: BVM before and during naloxone
  • Naloxone reverses opioid overdose: Titrate to respiratory drive
  • Fentanyl may require higher doses: More potent, may need repeated dosing
  • Observe for renarcotization: Opioid may outlast naloxone
  • Consider polysubstance use: Benzos, alcohol, stimulants common
  • Harm reduction saves lives: Prescribe take-home naloxone at discharge

Classic Toxidrome

FeatureFinding
Mental statusDepressed (drowsy to comatose)
PupilsPinpoint (miosis)
RespirationsSlow, shallow, apnea
SkinCyanosis if hypoxic

Emergency Treatments

RouteNaloxone DoseNotes
Intranasal4 mg (2 mg per nostril)First-line prehospital
Intramuscular0.4-2 mgIf no IV
Intravenous0.04-0.4 mg initialTitrate; start low in opioid-dependent
Repeatq2-3 min if no responseUp to 10 mg total

Definition

Overview

Opioid overdose is a life-threatening emergency characterized by CNS and respiratory depression due to excessive opioid effect. It is a leading cause of drug-related death in the United States, with synthetic opioids (primarily illicit fentanyl) now responsible for most overdose fatalities. Prompt recognition and naloxone administration save lives.

Classification

By Opioid Type:

CategoryExamples
NaturalMorphine, codeine
Semi-syntheticHeroin, oxycodone, hydrocodone, hydromorphone
SyntheticFentanyl, methadone, tramadol
Partial agonistBuprenorphine

By Setting:

TypeContext
Illicit drug useHeroin, illicit fentanyl
Prescription misuseOpioid analgesics
IatrogenicHospital setting, post-operative
Accidental (pediatric)Ingestion of medications

Epidemiology

  • US overdose deaths: >100,000/year total; >70,000 involve opioids
  • Fentanyl predominates: Most opioid deaths involve synthetic opioids
  • Rising trend: Overdose deaths continue to increase
  • Risk populations: IVDU, chronic pain patients, post-incarceration, polysubstance users

Etiology

Risk Factors:

FactorMechanism
Fentanyl contaminationUnpredictable potency
Tolerance lossAfter abstinence (detox, incarceration)
Combining with sedativesAdditive CNS/respiratory depression
High-dose prescriptionExceeding tolerance
Opioid-naïveNo tolerance
Respiratory comorbiditiesCOPD, sleep apnea

Pathophysiology

Mechanism of Opioid Toxicity

  1. Mu-opioid receptor binding: CNS, respiratory centers
  2. Respiratory depression: Decreased drive, rate, depth
  3. Hypoxia: Leading to loss of consciousness
  4. Apnea and death: If untreated

Other Opioid Effects

SystemEffect
CNSSedation, euphoria, coma
RespiratoryHypoventilation, apnea
CardiovascularBradycardia, mild hypotension
GIDecreased motility, nausea
PupilsMiosis (pinpoint)
UrinaryRetention

Duration of Action

OpioidDuration
Heroin4-6 hours
Fentanyl (IV)30-60 minutes
Methadone24-36 hours
Extended-release formulations12-24+ hours

Naloxone duration: 30-90 minutes → Risk of renarcotization


Clinical Presentation

Classic Opioid Toxidrome

Triad:

  1. Depressed level of consciousness
  2. Miosis (pinpoint pupils)
  3. Respiratory depression

Other Findings

History (Often Limited)

Key Information:

Physical Examination

FindingSignificance
UnresponsiveSevere overdose
Apnea/Agonal breathingImminent death
Pinpoint pupilsClassic; may be absent with coingestants
CyanosisHypoxia
Track marksIVDU
Pulmonary cracklesNCPE possible

Hypoxia (low SpO2)
Common presentation.
Cyanosis
Common presentation.
Bradycardia
Common presentation.
Hypotension (usually mild)
Common presentation.
Hypothermia
Common presentation.
Decreased bowel sounds
Common presentation.
Pulmonary edema (non-cardiogenic, NCPE)
Common presentation.
Needle marks (IVDU)
Common presentation.
Red Flags

Life-Threatening Features

FindingConcernAction
ApneaRespiratory arrestImmediate BVM + naloxone
CyanosisSevere hypoxiaVentilate, high-flow O2
UnresponsiveProfound overdoseFull resuscitation
Cardiac arrestHypoxic arrestCPR + naloxone + ACLS
Pulmonary edemaNCPEVentilatory support
No response to naloxonePolysubstance, wrong diagnosisReassess

Complications

  • Aspiration pneumonia
  • Hypoxic brain injury
  • Rhabdomyolysis (prolonged immobility)
  • Compartment syndrome
  • Death

Differential Diagnosis

Other Causes of Depressed LOC with Respiratory Depression

DiagnosisFeatures
Benzodiazepine overdoseSimilar; may have mixed use
Ethanol intoxicationAlcohol on breath
GHB/Sedative-hypnoticsSimilar presentation
HypoglycemiaLow glucose; reverses with dextrose
StrokeFocal deficits
Head traumaMechanism, focal findings
SepsisFever, infection source
HypothermiaLow temperature
Carbon monoxideExposure history

Diagnostic Approach

Clinical Diagnosis

  • Opioid overdose is a clinical diagnosis
  • Classic toxidrome + response to naloxone = diagnostic

Bedside Assessment

TestPurpose
SpO2Assess hypoxia
Fingerstick glucoseRule out hypoglycemia
TemperatureHypothermia
ECGArrhythmia (methadone: QT prolongation)

Laboratory Studies

TestPurpose
ABG/VBGHypercapnia, acidosis
BMPRenal function (for rhabdomyolysis)
CKRhabdomyolysis
Urine drug screenConfirms opioid (may miss fentanyl)
Acetaminophen, salicylateRule out coingestants
LactatePerfusion status

Important Note on Urine Drug Screens

  • Fentanyl often NOT detected on standard screens
  • Do NOT rely on UDS to rule out opioid overdose
  • Treat based on clinical presentation

Treatment

Principles

  1. Airway and ventilation first: BVM before/during naloxone
  2. Naloxone administration: Titrate to respiratory drive
  3. Supportive care: IV access, monitoring
  4. Observe for renarcotization: Opioid may outlast naloxone
  5. Address polydrug use: Other substances may require treatment

Airway Management

Before and During Naloxone:

  • Head tilt-chin lift or jaw thrust
  • Suction if needed
  • BVM with 100% O2
  • Avoid hyperventilation

Intubation Indications:

  • Persistent apnea despite naloxone
  • Unable to protect airway
  • Aspiration
  • Refractory hypoxemia

Naloxone (Narcan)

Mechanism: Competitive mu-opioid receptor antagonist

Dosing by Route:

RouteDoseNotes
Intranasal4 mg (2 mg per nostril)Easiest prehospital
Intramuscular0.4-2 mgIf no IV
Intravenous0.04-0.4 mg initialStart low in opioid-dependent
Subcutaneous0.4-2 mgAlternative
Endotracheal2-4 mg (diluted)If no other access

Titration Strategy:

  • Start low (0.04-0.1 mg IV) in opioid-dependent patients
  • Goal: Restore respiratory drive, NOT full arousal
  • Repeat every 2-3 minutes up to 10 mg
  • If no response after 10 mg: Reconsider diagnosis

Fentanyl Overdose:

  • May require higher and repeated doses
  • Maintain ventilation while titrating

Observation Period

Opioid TypeDuration
Short-acting (heroin)4-6 hours
Long-acting (methadone)12-24 hours
Fentanyl patchProlonged
Extended-release12-24+ hours

Naloxone Infusion

Indication: Recurrent respiratory depression

Preparation: 2/3 of effective bolus dose per hour

  • Example: 0.4 mg reversed → Infuse ~0.25-0.3 mg/hour

Managing Precipitated Withdrawal

SymptomManagement
AgitationReassurance, benzodiazepines if severe
VomitingAntiemetics, protect airway
DiaphoresisSupportive
PainNon-opioid analgesics if possible

Supportive Care

InterventionDetails
IV fluidsFor hypotension, rhabdomyolysis
ECGQT prolongation (methadone)
MonitoringContinuous SpO2, cardiac
Chest X-rayIf aspiration suspected
CK monitoringIf prolonged immobility

Disposition

Discharge Criteria

  • Observed minimum 4-6 hours (longer for long-acting opioids)
  • No recurrent respiratory depression after naloxone wears off
  • Stable mental status
  • No complications
  • Safe discharge plan
  • Naloxone kit prescribed

Admission Criteria

  • Long-acting opioid ingestion
  • Repeated naloxone doses required
  • Naloxone infusion needed
  • Respiratory complications
  • Rhabdomyolysis
  • Persistent altered mental status
  • Unknown coingestants

ICU Admission

  • Intubated patient
  • Hemodynamic instability
  • Severe complications

Leaving AMA

  • Document capacity
  • Provide naloxone kit
  • Harm reduction counseling
  • Provide addiction treatment resources

Harm Reduction at Discharge

  • Prescribe naloxone (Narcan) for patient and family
  • Overdose prevention education
  • Offer treatment for opioid use disorder (buprenorphine initiation)
  • Connect with addiction services

Patient Education

For Patient

  • "You had an opioid overdose—the drug slowed your breathing and you could have died."
  • "Naloxone saved your life."
  • "Please carry naloxone and teach others how to use it."
  • "Treatment for opioid use disorder is available and works."

Overdose Prevention

  • Never use alone
  • Start low after tolerance break
  • Avoid mixing opioids with benzos/alcohol
  • Test substances (fentanyl test strips)
  • Carry naloxone

How to Use Naloxone (Teach Patient/Family)

  1. Check responsiveness
  2. Call 911
  3. Give naloxone (nasal spray or injection)
  4. Perform rescue breathing
  5. Place in recovery position
  6. Stay until help arrives

Warning Signs of Overdose

  • Unresponsive, can't wake up
  • Slow or stopped breathing
  • Gurgling or snoring sounds
  • Blue lips or fingertips

Special Populations

Opioid-Dependent Patients

  • Start with lower naloxone doses (0.04-0.1 mg)
  • Titrate to respiratory drive, not full alertness
  • Avoid severe withdrawal (agitation, vomiting → aspiration)

Pregnancy

  • Naloxone is safe and indicated
  • May precipitate fetal withdrawal
  • OB consultation
  • Monitor for fetal distress

Pediatric

  • Accidental ingestion common
  • Naloxone: 0.1 mg/kg IV/IM/IN (max 2 mg)
  • Repeat as needed

Cardiac Arrest

  • Standard ACLS + Naloxone 2 mg IV/IO
  • Airway and ventilation critical
  • Continue CPR

Quality Metrics

Performance Indicators

MetricTargetRationale
Naloxone given for suspected OD100%Life-saving
Observation adequate for opioid duration100%Prevent renarcotization
Naloxone kit prescribed at discharge>0%Harm reduction
OUD treatment offered100%Reduce future overdoses

Documentation Requirements

  • Suspected substance and route
  • Prehospital naloxone and response
  • Hospital naloxone doses and response
  • Observation period
  • Discharge plan and harm reduction

Key Clinical Pearls

Diagnostic Pearls

  • Classic triad: Depressed LOC + miosis + respiratory depression
  • Miosis may be absent: Meperidine, coingestants, hypoxia
  • UDS misses fentanyl: Treat clinically
  • Response to naloxone is diagnostic
  • Polysubstance is common: May have atypical features

Treatment Pearls

  • Ventilate first, then give naloxone: BVM is life-saving
  • Start low in dependent patients: Avoid severe withdrawal
  • Titrate to respiratory drive, not consciousness
  • Fentanyl may need high/repeated doses: Keep ventilating
  • Renarcotization is real: Observe 4-6+ hours

Disposition Pearls

  • Must observe after reversal: Opioid outlasts naloxone
  • Prescribe take-home naloxone: To every overdose patient
  • Offer OUD treatment: ED-initiated buprenorphine saves lives
  • Document, counsel, connect: Comprehensive approach

References
  1. Boyer EW. Management of Opioid Analgesic Overdose. N Engl J Med. 2012;367(2):146-155.
  2. Schiller EY, et al. Opioid Overdose. StatPearls. 2024.
  3. Chou R, et al. Management of Suspected Opioid Overdose With Naloxone in Out-of-Hospital Settings. Ann Intern Med. 2017;167(12):867-875.
  4. CDC. Opioid Overdose Prevention. 2024.
  5. SAMHSA. Opioid Overdose Prevention Toolkit. 2018.
  6. American College of Emergency Physicians. Naloxone Prescribing Policy Statement. 2019.
  7. D'Onofrio G, et al. Emergency Department-Initiated Buprenorphine/Naloxone Treatment for Opioid Dependence. JAMA. 2015;313(16):1636-1644.
  8. UpToDate. Acute opioid intoxication in adults. 2024.

At a Glance

EvidenceStandard
Last UpdatedRecently

Guidelines

  • NICE Guidelines
  • BTS Guidelines
  • RCUK Guidelines