Behavioral Health

Opioid overdose: recognition and naloxone management

Clinical Overview and When to Suspect Opioid Overdose

— Leading cause of accidental death in US adults; >75% of drug overdose deaths involve opioids

— Fentanyl and fentanyl analogs now dominate (illicitly manufactured; often contaminating heroin, counterfeit pills "M30s," cocaine, methamphetamine)

— Xylazine ("tranq") and benzodiazepines increasingly co-detected → naloxone-refractory sedation after opioid reversal

— Unresponsive patient, RR <12 or apneic, pinpoint pupils

— Found down, drug paraphernalia present, track marks, transdermal patches

— Postoperative oversedation, especially with PCA pump errors, sleep apnea, or basal-rate infusions

— Pediatric exposure: methadone or buprenorphine ingestion at home (one pill can kill a toddler)

— Chronic pain patient on high MME (morphine milligram equivalents) with new sedatives, alcohol, or CYP3A4 inhibitor added

— Recent abstinence (incarceration release, post-detox, post-rehab) → lost tolerance

— Concurrent benzodiazepines, alcohol, gabapentinoids, or sleep apnea

— Methadone initiation/titration (long, variable half-life 8–59 h; QT prolongation)

— Injection use, solo use, prior nonfatal overdose

Board pearl: The classic toxidrome of miosis + respiratory depression + obtundation is the highest-yield trigger to give empiric naloxone before any labs return. Do not wait for a urine drug screen — it neither rules in nor rules out fentanyl in most hospital assays, and management is clinical. In any "unresponsive adult, RR 6, pinpoint pupils" stem, the next best step is naloxone plus bag-valve-mask ventilation, never intubation first.

Definition: Life-threatening toxidrome from excess opioid agonism at mu receptors, producing the classic triad of CNS depression, respiratory depression, and miosis. Death is from hypoventilation-induced hypoxemia, not hemodynamic collapse.

Epidemiology and trends:

When to suspect in the ED or CCS case:

Risk factors for fatal overdose:

Presentation Patterns and Key History

— Substance: heroin, fentanyl, oxycodone, methadone, buprenorphine, tramadol, loperamide (massive doses), codeine

— Route: IV, intranasal "snorted," smoked, transdermal patch (chewed or heated), oral

— Time of last use, co-ingestants (alcohol, benzos, stimulants, xylazine)

— Prior overdoses, naloxone responsiveness, OUD treatment status (methadone clinic, buprenorphine Rx)

— Recent release from incarceration, detox, or hospitalization → tolerance loss

— Access to prescription opioids at home; pediatric or geriatric household members

— Heroin/fentanyl IV: rapid onset within minutes, classic triad, responds to standard naloxone but fentanyl often needs repeat or higher doses

— Methadone: delayed peak (3–4 h), prolonged toxicity 24–48 h, QT prolongation → torsades, requires extended observation

— Buprenorphine: ceiling effect on respiratory depression in adults; rarely fatal alone but dangerous in opioid-naïve children and with co-sedatives; partial agonism may need higher naloxone doses (≥2 mg)

— Tramadol: seizures, serotonin syndrome, less miosis

— Loperamide abuse: wide QRS, torsades, cardiac arrest from sodium channel blockade

— Diphenoxylate/atropine (Lomotil): biphasic — anticholinergic first, then opioid toxicity

Step 3 management: In a stem describing a methadone-maintained patient with new respiratory depression after starting an antibiotic, suspect a CYP3A4 inhibitor interaction (erythromycin, clarithromycin, fluconazole, ritonavir). The right answer is naloxone now, then review medication reconciliation and obtain an ECG for QTc before resuming methadone.

Classic presentation: Witnessed or unwitnessed unresponsiveness with shallow, slow, or agonal breathing. Bystanders may describe gurgling/snoring respirations ("death rattle") — a sign of impending respiratory arrest.

History elements to obtain (collateral if patient obtunded):

Distinct clinical patterns:

Postoperative/iatrogenic: PCA pump, neuraxial morphine (delayed respiratory depression up to 24 h), patch overdose in febrile patient (accelerated absorption)

Physical Exam Findings and Hemodynamic Assessment

— Respiratory rate <12 (often 4–8); shallow tidal volumes; SpO₂ <90% on room air

— Bradycardia and mild hypotension from hypoxemia and decreased sympathetic tone (not primary cardiovascular toxicity)

— Hypothermia from environmental exposure if found down

— Hyperthermia suggests co-ingestion (cocaine, meth, serotonin syndrome from tramadol/meperidine) or aspiration pneumonia

— GCS often 3–8; pupils pinpoint (1–2 mm), reactive — preserved reactivity distinguishes from brainstem stroke

— Mydriasis does NOT exclude opioid overdose: severe hypoxia, co-ingested stimulants, meperidine, tramadol, or post-naloxone state

— Hyporeflexia, decreased tone; no focal deficits — focal signs mandate stroke workup

— Diminished breath sounds, slow/agonal pattern

— Rales/frothy pink sputum → naloxone-associated or opioid-induced noncardiogenic pulmonary edema (occurs in 0.2–10%)

— Aspiration pneumonitis from emesis

— Track marks, abscesses, cellulitis at injection sites; endocarditis stigmata (Janeway lesions, Osler nodes, splinter hemorrhages)

— Skin popping scars, transdermal patches (check back, buttocks, axillae — "patch hunting")

— Necrotic eschars on extremities → xylazine-associated wounds even at non-injection sites

— Compartment syndrome from prolonged immobility → rhabdomyolysis

Key distinction: Opioid overdose causes bradypnea with normal-to-pinpoint pupils; clonidine and organophosphate toxidromes can mimic miosis + CNS depression, but organophosphates add SLUDGE/muscarinic excess and clonidine produces transient hypertension then bradycardia. Always inspect skin for fentanyl patches — undiscovered patches are a classic CCS "missed source" item that prolongs the case.

Vital signs:

Neuro:

Pulmonary:

Skin and extremities:

Cardiac: Listen for new murmurs (IE), check for pulses (PEA arrest is common terminal rhythm).

Diagnostic Workup — Initial Labs, Imaging, ECG

— Fingerstick glucose (always — hypoglycemia mimics any altered mental status)

— Pulse oximetry and capnography (EtCO₂): EtCO₂ >50 confirms hypoventilation and trends response to naloxone

— ABG/VBG: respiratory acidosis (acute, pH <7.3, PaCO₂ >50, normal HCO₃); mixed picture if lactic acidosis from hypoperfusion

— CBC, BMP, LFTs, lipase

— CK — rhabdomyolysis from prolonged down-time (CK >5000 → aggressive IV fluids)

— Lactate (tissue hypoxia)

— Acetaminophen and salicylate levels in any intentional overdose — co-ingestion is the rule

— Ethanol level; pregnancy test in reproductive-age women

— Troponin if prolonged hypoxia or chest pain (demand ischemia, IE)

— Blood cultures ×2 if febrile or injection drug user (IDU) — don't miss endocarditis

— Standard immunoassays miss fentanyl, methadone, oxycodone, tramadol, buprenorphine unless specifically ordered

— UDS is not required to give naloxone and a negative screen does not exclude overdose

— Useful for documentation and to guide MAT counseling, not acute management

— QTc prolongation with methadone, loperamide (also wide QRS), or co-ingestants

— Sinus bradycardia common; look for ischemia from hypoxia

— CXR: aspiration, noncardiogenic pulmonary edema (bilateral fluffy infiltrates, normal heart size)

— Non-contrast head CT if persistent altered mental status after naloxone or focal deficits — rule out hemorrhage, anoxic injury

— Consider CT abdomen if body packer/stuffer suspected (radiopaque packets)

CCS pearl: In the CCS interface, after empiric naloxone and oxygen, order fingerstick glucose, ABG, ECG, CXR, acetaminophen/salicylate levels, and CK simultaneously. Forgetting the acetaminophen level in an intentional overdose is a high-frequency CCS deduction.

Resuscitation comes before diagnostics — do not delay naloxone or BVM ventilation for testing. Once stabilized, obtain:

Point-of-care:

Labs:

Urine drug screen (UDS):

ECG:

Imaging:

Diagnostic Workup — Advanced or Confirmatory Studies

— Persistent coma after naloxone reversal of respiratory depression → look beyond opioids

— Refractory hypoxemia → ARDS, aspiration, pulmonary edema

— Hemodynamic instability disproportionate to overdose → sepsis, endocarditis, cardiogenic shock

— Send-out comprehensive toxicology (GC-MS or LC-MS/MS) for fentanyl analogs, novel synthetics, xylazine, nitazenes — results return days later, valuable for forensic and public health surveillance, not acute care

— Xylazine testing is not routine; suspect clinically when sedation persists despite full naloxone reversal of opioid effects in a patient with characteristic necrotic ulcers

— Repeat ECG and continuous telemetry if methadone or loperamide involved (delayed torsades)

— Echocardiogram (TTE → TEE if negative) in IDU with fever, bacteremia, or new murmur — modified Duke criteria for endocarditis

— Blood cultures ×2–3 sets before antibiotics

— MRI brain if prolonged anoxic injury suspected (bilateral basal ganglia, watershed infarcts, delayed post-hypoxic leukoencephalopathy)

— EEG if seizures (tramadol, meperidine, fentanyl-induced rigid chest) or non-convulsive status

— Bronchoscopy rarely indicated unless massive aspiration

— Abdominal CT or radiograph for body packers (wrapped packets, typically transporting drugs) vs body stuffers (hastily swallowed during arrest) — packers need surgical/whole-bowel irrigation planning; stuffers usually conservative observation

— Many states require overdose case reporting to health departments; ED toxicology may notify medical examiner if death occurs

— Consider engaging harm reduction services for fentanyl test strip distribution

Board pearl: A patient who remains comatose after respiratory rate normalizes with naloxone almost certainly has co-ingestion (benzodiazepines, alcohol, xylazine) or anoxic brain injury, not inadequate naloxone dosing. Don't keep escalating naloxone — escalate the workup. Order head CT, glucose, ammonia, and consider EEG.

When to escalate testing:

Specific confirmatory and adjunctive studies:

Procedural diagnostics:

Public health and surveillance:

Risk Stratification and First-Line Management Logic

— Airway: jaw thrust, oral/nasal airway, suction emesis

— Breathing: bag-valve-mask with 100% O₂ — this alone reverses hypoxia and is the most important intervention; naloxone is adjunctive

— Circulation: IV access ×2, monitor, telemetry

— Dextrose, naloxone, thiamine — the "coma cocktail" tailored to clinical picture

— Goal: adequate ventilation (RR ≥12, SpO₂ >92%), NOT full alertness

— Initial dose 0.04–0.4 mg IV (dilute 0.4 mg in 10 mL saline; give 1 mL aliquots) in opioid-tolerant or chronic pain patients to avoid precipitated withdrawal

— 0.4–2 mg IV/IM/IN in apneic or peri-arrest patients

— Repeat every 2–3 minutes, doubling dose, up to 10 mg total before reconsidering diagnosis

— Routes if no IV: IM, intranasal (4 mg/spray), nebulized if spontaneously breathing

— Recurrent respiratory depression after initial reversal (long-acting opioid: methadone, extended-release oxycodone, fentanyl patch, body packer)

— Infusion rate = ⅔ of the effective bolus dose per hour (e.g., 2 mg bolus worked → 1.3 mg/h)

— Titrate to RR ≥12; observe ≥6–12 h after stopping for re-sedation

— Short-acting opioid (heroin, fentanyl) with full reversal, normal mentation, ambulatory, normal SpO₂ on room air × 1–2 h post-naloxone → consider discharge with services

— Long-acting opioid → admit for ≥24 h monitoring

— Any patch, methadone, sustained-release → admit, telemetry

Step 3 management: Never intubate first when opioid overdose is suspected and the patient has a pulse — a bag and a dose of naloxone almost always avoid intubation. Intubation is reserved for failed BVM, aspiration with hypoxemia, or co-toxin requiring prolonged airway protection.

Immediate priorities (ABCs, parallel processing):

Naloxone dosing strategy — start LOW in spontaneously breathing patients:

When to start a naloxone infusion:

Observation period:

Pharmacotherapy — Naloxone in Depth

— IV: 0.04–2 mg; titrate

— IM: 0.4–2 mg (autoinjector 2 mg)

— Intranasal: 4 mg or 8 mg per spray (Narcan, Kloxxado) — preferred for bystander/EMS use

— Pediatric: 0.01 mg/kg initial, up to 0.1 mg/kg if needed; bystander IN dose same as adult

— Symptoms: agitation, nausea, vomiting, diaphoresis, piloerection, mydriasis, tachycardia, hypertension, diarrhea, yawning, lacrimation

— Treat with antiemetics (ondansetron), IV fluids, clonidine for autonomic symptoms; do NOT give more opioid

— Avoid combative situations: restraints only if needed; provide reassurance

— Buprenorphine overdose (rare, usually pediatric or polysubstance): high mu affinity → may need 2–10 mg naloxone and continuous infusion

— Methadone, fentanyl patches, sustained-release oxycodone: plan for infusion + prolonged observation

— Pentazocine, nalbuphine (kappa agonists): naloxone effective

— Loperamide cardiotoxicity: naloxone reverses CNS/respiratory effects but NOT QRS widening → give sodium bicarbonate for wide QRS, magnesium for torsades

— Clonidine overdose mimicking opioid toxidrome: may partially respond to high-dose naloxone but mainstay is supportive care

— Supplemental O₂, antiemetics, IV fluids

— Avoid flumazenil empirically — seizure risk in chronic benzo users

— Activated charcoal only if recent (<1 h) large oral ingestion AND protected airway

Board pearl: Choose the lowest naloxone dose that restores adequate ventilation, not consciousness. A "fully awake but vomiting and agitated" patient post-naloxone is a teaching example of iatrogenic precipitated withdrawal — the correct answer on Step 3 is "titrate naloxone to respiratory effort, not GCS."

Mechanism: Competitive mu-opioid receptor antagonist; also blocks kappa and delta. Onset 1–2 min IV, 2–5 min IM/IN. Half-life 30–90 min — shorter than most opioids, hence re-sedation risk.

Formulations and dosing:

Precipitated withdrawal — anticipate and manage:

Special pharmacologic scenarios:

Adjuncts:

Procedures and Expanded Management

— BVM with OPA/NPA + naloxone is first-line — successful in >90%

— Endotracheal intubation if: failed BVM, massive aspiration with hypoxemia, refractory to naloxone, need for prolonged ventilation, concurrent ARDS, or co-ingestion requiring airway protection

— RSI considerations: etomidate or ketamine for induction; succinylcholine if no contraindication; avoid sedation that worsens hemodynamics

— Calculate hourly dose = (effective bolus dose) × (2/3) per hour

— Mix 4 mg in 250 mL D5W or NS = 16 mcg/mL

— Titrate to RR ≥12 and SpO₂ ≥92%; bolus half the initial effective dose if breakthrough

— Continue ≥12–24 h depending on opioid half-life; wean by 50% every 2–4 h

— Remove transdermal fentanyl patches — including hidden ones (oral, axilla, behind ears in pediatrics)

— Wash skin of contaminated patients (large fentanyl spill — rare true dermal absorption risk)

— Whole-bowel irrigation with polyethylene glycol for confirmed body packers (asymptomatic transporters) until packets clear; surgical removal if obstruction, leak (massive toxicity), or perforation

— IV fluids for hypotension and rhabdomyolysis (target UOP 1–2 mL/kg/h)

— Sodium bicarbonate for QRS >100 ms (loperamide, propoxyphene)

— Magnesium 2 g IV for torsades (methadone)

— Vasopressors rarely needed; if so, norepinephrine first-line

— Antibiotics if aspiration pneumonia (ceftriaxone + consideration of anaerobic coverage)

— Buprenorphine induction when patient in mild-moderate withdrawal (COWS ≥8) is now standard of care after non-fatal overdose — reduces 30-day mortality and re-overdose

— Methadone single dose for symptom relief permitted in ED without X-waiver (now eliminated under MAT Act 2023 — any DEA-licensed prescriber can Rx buprenorphine)

CCS pearl: After stabilizing a heroin overdose patient, the highest-yield orders are: take-home naloxone Rx, buprenorphine induction or warm handoff to addiction medicine, hepatitis C and HIV testing, and connection to syringe service program — these are increasingly tested as Step 3 quality measures.

Airway management decision tree:

Naloxone infusion protocol (CCS-ready):

Decontamination:

Adjunctive interventions:

MAT initiation in the ED:

Special Populations — Elderly and Renal/Hepatic Impairment

— Iatrogenic overdose is the dominant pattern: post-op opioids, chronic pain regimens, accidental double-dosing in dementia, drug-drug interactions

— Decreased lean body mass, reduced hepatic clearance, lower respiratory reserve → start opioids at 25–50% of adult dose

— High-risk co-prescribing: opioid + benzodiazepine + gabapentinoid ("trinity") — FDA black box for respiratory depression

— Sleep apnea (often undiagnosed) amplifies risk

— Falls secondary to opioid sedation cause fractures, head injury

— Morphine → active metabolite morphine-6-glucuronide accumulates → prolonged sedation, respiratory depression in CKD/AKI; avoid in eGFR <30

— Codeine, meperidine, tramadol: avoid — accumulating metabolites cause toxicity and seizures (normeperidine)

— Hydromorphone, fentanyl, methadone, buprenorphine are preferred in renal disease (no significant active renal metabolites)

— Naloxone itself is hepatically metabolized — no renal dose adjustment

— Reduced first-pass and clearance → prolonged duration of all opioids and naloxone

— Use lower doses, longer intervals; monitor closely

— Methadone and buprenorphine require careful titration; avoid combination with acetaminophen-containing products in cirrhosis

— CYP3A4 inhibitors (clarithromycin, fluconazole, ritonavir, diltiazem, grapefruit) ↑ fentanyl, methadone, oxycodone levels

— CYP2D6 variants: ultra-rapid metabolizers convert codeine → morphine excessively (pediatric deaths post-tonsillectomy → FDA contraindication <12 yo)

— SSRIs/SNRIs + tramadol or meperidine → serotonin syndrome

Step 3 management: For an 82-year-old post-hip-fracture patient with new confusion and RR 8 after starting oxycodone + lorazepam, the answer is discontinue benzodiazepine, reduce opioid dose by 50%, switch to scheduled acetaminophen plus low-dose hydromorphone, and give a naloxone trial 0.04 mg IV — not full reversal, which precipitates pain crisis.

Elderly patients:

Renal impairment:

Hepatic impairment:

Polypharmacy interactions:

Special Populations — Pregnancy, Pediatrics, and Others

— Naloxone is given without hesitation in an overdosing pregnant patient — maternal hypoxia harms the fetus more than transient withdrawal

— Anticipate uterine contractions and preterm labor from precipitated withdrawal; place on tocodynamometry and continuous fetal monitoring after 23 weeks

— Do NOT detox opioid-dependent pregnant patients — withdrawal causes fetal distress and miscarriage

— Methadone or buprenorphine MAT is standard throughout pregnancy; buprenorphine-mono (Subutex) preferred over combo (Suboxone) historically, though combo now acceptable

— Neonate observed for neonatal opioid withdrawal syndrome (NOWS) — supportive care, morphine or methadone if Finnegan score persistently elevated

— Exploratory ingestion of methadone, buprenorphine, oxycodone — "one pill can kill"

— Lipophilic patches (fentanyl, buprenorphine) chewed or stuck on skin

— Symptoms: lethargy, miosis, bradypnea, hypothermia, hypotonia

— Naloxone 0.1 mg/kg IV/IO/IM/IN (max 2 mg/dose); repeat; consider infusion for methadone/buprenorphine ingestion

— Admit all pediatric opioid exposures ≥24 h regardless of initial appearance

— Mandatory child protective services referral for unsafe access

— Counterfeit "Percocet" or "Xanax" laced with fentanyl — leading cause of teen overdose deaths

— Screen with CRAFFT; consider buprenorphine MAT (FDA-approved ≥16 yo)

— Tolerance lowers naloxone threshold for withdrawal; titrate carefully

— Co-prescribe take-home naloxone for any patient on ≥50 MME/day or any opioid + benzodiazepine

Board pearl: A toddler found sleepy after visiting grandma's house — check the medicine cabinet for methadone, buprenorphine, clonidine, and sulfonylureas. Give naloxone, fingerstick glucose, ECG, and admit for ≥24 hours even if alert in the ED, because methadone/buprenorphine have delayed and prolonged effects in children.

Pregnancy:

Pediatrics:

Adolescents:

Patients with chronic pain on long-term opioids:

Complications and Adverse Outcomes

— Aspiration pneumonitis/pneumonia — emesis + obtundation; treat with supportive care, antibiotics if secondary bacterial infection

— Noncardiogenic pulmonary edema (NCPE): bilateral infiltrates, frothy sputum, normal LV function — supportive O₂/PEEP; usually resolves in 24–48 h

— ARDS from prolonged hypoxia or aspiration

— Acute respiratory failure requiring mechanical ventilation

— Hypoxic-ischemic brain injury — the most feared sequela; correlates with down-time and arrest

— Delayed post-hypoxic leukoencephalopathy — recovery then deterioration days to weeks later, MRI shows symmetric white matter changes

— Seizures (tramadol, meperidine, fentanyl-induced chest wall rigidity, hypoxia)

— Compartment syndrome from prolonged immobility → nerve injury, contractures

— Bradydysrhythmias, asystole/PEA arrest from hypoxia

— QT prolongation, torsades (methadone, loperamide)

— Wide-complex tachycardia (loperamide, propoxyphene)

— Demand ischemia, type 2 MI

— Rhabdomyolysis → AKI; aggressive crystalloid resuscitation

— Lactic acidosis from hypoperfusion

— Hyperkalemia from rhabdo

— Skin/soft tissue infections, abscesses, necrotizing fasciitis

— Endocarditis (often right-sided, tricuspid, S. aureus including MRSA)

— Septic arthritis, vertebral osteomyelitis, epidural abscess

— HIV, HCV, HBV transmission; tetanus, wound botulism (black tar heroin)

— Xylazine-associated skin necrosis at and away from injection sites — multidisciplinary wound care

— Precipitated withdrawal, vomiting, aspiration, takotsubo cardiomyopathy, rare flash pulmonary edema, sympathetic surge

Key distinction: Anoxic brain injury vs delayed post-hypoxic leukoencephalopathy — the former is acute and presents at ED arrival; the latter occurs days to weeks after apparent recovery, with cognitive decline and parkinsonism. MRI shows diffuse white matter demyelination. Both are devastating and emphasize the value of early bystander naloxone.

Respiratory:

Neurologic:

Cardiovascular:

Renal and metabolic:

Infectious (in IDU):

Wound complications:

Iatrogenic from naloxone:

When to Escalate Care — ICU, Consult, Inpatient Triage

— Requirement for mechanical ventilation or persistent hypoxemia

— Naloxone infusion in progress

— Hemodynamic instability, vasopressor support

— Methadone, loperamide, or QT-prolonging overdose with arrhythmia or QTc >500

— Status post-cardiac arrest with ROSC — initiate targeted temperature management 32–36°C × 24 h if comatose

— Severe rhabdomyolysis with AKI requiring renal replacement consideration

— ARDS, multi-lobar aspiration pneumonia

— Body packers awaiting whole-bowel irrigation/surgery

— Long-acting opioid ingestion (methadone, sustained-release) without active arrhythmia → 24 h telemetry

— Transdermal patch overdose post-removal — telemetry until SpO₂ stable >12 h off naloxone

— Stable on low-dose naloxone infusion approaching wean

— Aspiration pneumonia without ARDS, stable

— Endocarditis without hemodynamic compromise (with ID and CT surgery consultation)

— Cellulitis/abscess requiring IV antibiotics

— Toxicology / Poison Control (1-800-222-1222) — early for body packers, loperamide, novel synthetics, infusion management

— Addiction Medicine / Psychiatry — MAT initiation, safety planning, dual diagnosis

— Social work and case management — housing, syringe services, transportation to follow-up

— Infectious Disease for endocarditis, HIV/HCV linkage to care

— Cardiothoracic Surgery for valve replacement in IE with indications

— Ambulatory, RR ≥12, SpO₂ ≥95% on RA, GCS 15, no co-ingestants requiring obs

— ≥1–2 h post-last-naloxone-dose

— Accompanied by sober adult, take-home naloxone given, MAT offered, follow-up arranged

CCS pearl: In a CCS case, after stabilizing the overdose, change location to telemetry or ICU rather than discharging from the ED if methadone, patch, or sustained-release is suspected. Premature discharge to the floor or home before the end of the opioid's pharmacologic effect is a frequent CCS penalty.

ICU admission criteria:

Step-down/telemetry indications:

General medical floor:

Consultations to engage:

Discharge from ED criteria (for isolated short-acting opioid overdose):

Key Differentials — Same-Category (Other Sedative/CNS-Depressant) Causes

— CNS depression, normal or mildly depressed respirations (rarely apneic alone), normal pupils, often hyporeflexia

— Distinguishing feature: respirations relatively preserved unless co-ingested with opioids or alcohol

— Flumazenil reversal is controversial — avoid in chronic benzo users or unknown co-ingestion (seizure risk)

— Slurred speech, ataxia, nystagmus, normal-to-large pupils, characteristic odor

— Respiratory depression at very high BAC (>400 mg/dL)

— Treat supportively; thiamine before glucose if malnourished (Wernicke prophylaxis)

— Profound CNS and respiratory depression, bullae on dependent skin, hypothermia, cardiovascular collapse

— Treat with urinary alkalinization (phenobarbital), hemodialysis if severe

— Profound but brief coma, often awakens spontaneously within hours

— Bradycardia, miosis can occur — mimics opioid overdose but does not respond to naloxone

— Mimics opioid toxidrome closely: miosis, bradypnea, hypotension, bradycardia, sedation

— Transient initial hypertension from peripheral α effect

— Variable, often poor response to naloxone

— Pediatric exposures common (eye drops, nasal sprays)

— Sedation, miosis, hypotension, tachycardia (anticholinergic), QT prolongation

— Anticholinergic toxidrome + wide QRS, terminal R in aVR, seizures — distinct from opioids

Key distinction: When a "classic opioid overdose" stem does NOT respond to escalating naloxone, think clonidine, GHB, or co-ingested benzodiazepine/alcohol. Clonidine in particular catches examinees because it produces near-identical pinpoint pupils and respiratory depression. Look for the transient hypertension, profound bradycardia, and history of ADHD/HTN medications in the home.

Benzodiazepine overdose:

Alcohol intoxication:

Barbiturate overdose (now rare):

GHB / GBL:

Clonidine and other α2 agonists (tizanidine, guanfacine, dexmedetomidine, imidazoline decongestants like tetrahydrozoline):

Antipsychotics (especially quetiapine, olanzapine):

Tricyclic antidepressants:

Key Differentials — Other-Category Causes of Altered Mental Status

Board pearl: Two pupils, one diagnosis: pinpoint pupils + respiratory depression = opioids until proven otherwise, but the two non-opioid mimics that win wrong answers are clonidine and pontine hemorrhage. A non-responsive pupillary exam, focal neurologic findings, or failure to respond to ≥10 mg naloxone should trigger an immediate head CT.

Hypoglycemia: Always check fingerstick glucose — diaphoresis, tachycardia, focal deficits possible; mimics any toxidrome.

Hypoxia from other causes: PE, pneumonia, pneumothorax — pulse oximetry and CXR clarify.

Hypercapnic respiratory failure (COPD): CO₂ narcosis presents with somnolence, miosis from hypercapnia/hypoxia — ABG distinguishes (chronic respiratory acidosis with compensation).

Stroke (especially pontine hemorrhage): Pinpoint pupils classically with pontine lesions — but with focal deficits, hyperthermia, decerebrate posturing. Head CT is mandatory if naloxone fails to reverse.

Seizure / postictal state: Tongue laceration, urinary incontinence, witnessed activity; postictal Todd's paralysis can mislead.

Meningitis/encephalitis: Fever, headache, nuchal rigidity, photophobia; LP after CT.

Hepatic encephalopathy: Cirrhosis stigmata, asterixis, elevated ammonia.

Uremic encephalopathy: Known CKD/ESRD, missed dialysis.

Toxic-metabolic encephalopathies: Hyponatremia, hypernatremia, hypercalcemia, hyperammonemia.

Carbon monoxide poisoning: Headache, nausea, cherry-red skin (rare), multiple household members affected, co-oximetry shows elevated COHb (pulse ox normal). Treat with 100% O₂ ± hyperbarics.

Anticholinergic toxidrome: "Hot as a hare, dry as a bone, red as a beet, blind as a bat, mad as a hatter" — mydriasis, tachycardia, dry skin, urinary retention — opposite of opioids.

Cholinergic toxidrome (organophosphates): Miosis + SLUDGE/killer Bs (bradycardia, bronchorrhea, bronchospasm) — treat with atropine and pralidoxime.

Wernicke encephalopathy: Ophthalmoplegia, ataxia, confusion in alcoholic — thiamine before glucose.

Psychogenic unresponsiveness: Resistance to eye opening, no physiologic abnormalities.

Secondary Prevention, Discharge Medications, Long-Term Plan

— Universal prescription for any patient with overdose, OUD diagnosis, ≥50 MME/day chronic opioid, opioid + benzodiazepine co-prescription, or household contacts of high-risk individuals

— Intranasal 4 mg is most user-friendly; two doses minimum per kit

— Train family/friends on recognition (RR <12, unresponsive, blue lips), administration, recovery position, calling 911, and rescue breathing

— Many states have standing orders allowing pharmacy dispensing without individual Rx

— Buprenorphine/naloxone (Suboxone) — partial agonist; office-based, sublingual; start in mild withdrawal (COWS ≥8) to avoid precipitated withdrawal; target maintenance dose typically 16 mg/day

– Low-dose induction ("Bernese method") allowed for fentanyl users to minimize precipitated withdrawal

– As of MAT Act 2023, no X-waiver required — any DEA-registered prescriber can prescribe

— Methadone — full agonist; only via federally licensed Opioid Treatment Programs (OTPs); useful for high tolerance, severe OUD; daily observed dosing initially

— Extended-release naltrexone (Vivitrol IM monthly) — opioid antagonist; requires 7–10 day opioid-free period before initiation to avoid precipitated withdrawal; adherence challenges

— HIV PrEP for high-risk IDU

— HCV treatment — direct-acting antivirals regardless of active use

— Vaccinations: HBV, HAV, tetanus, pneumococcal, influenza, COVID

— Mental health treatment (depression, PTSD, anxiety) — high comorbidity

— Fentanyl test strips

— Syringe service programs (clean needles)

— "Never use alone" messaging; 988 Suicide and Crisis Lifeline, Never Use Alone hotline (1-800-484-3731)

— Avoid mixing with benzodiazepines/alcohol

Step 3 management: The single highest-impact discharge intervention after non-fatal opioid overdose is ED-initiated buprenorphine with warm handoff to outpatient MAT — reduces 30-day mortality by ~40%. The wrong answer is "refer to outpatient" without bridging — buprenorphine should be prescribed and administered before discharge.

Take-home naloxone (THN):

Medications for Opioid Use Disorder (MOUD):

Comorbidity management:

Harm reduction:

Follow-Up, Monitoring, and Counseling

— Within 72 hours for MAT initiation visit (addiction medicine, primary care X-MAT prescriber)

— Weekly visits during induction/stabilization phase (first 4–6 weeks)

— Monthly once stable on maintenance

— Annual labs: LFTs (methadone, buprenorphine), pregnancy test, HIV/HCV/HBV serologies in IDU

— Urine drug screens at each visit — collaborative tool, not punitive; expect buprenorphine/methadone positive

— Treatment retention and self-reported use

— COWS or SOWS scores to assess withdrawal symptoms during titration

— ECG QTc at baseline, on methadone induction, with dose >100 mg/day, and with any QT-prolonging co-medications

— Mental health screening (PHQ-9, GAD-7, PCL-5)

— Pregnancy testing

— Relapse risk highest in first 4 weeks post-detox/overdose — emphasize tolerance loss

— Discuss tapering high-MME chronic opioid regimens for non-cancer pain per CDC 2022 guidelines — avoid abrupt cessation

— Safe storage and disposal of opioids — lockboxes, drug take-back days

— Naloxone refresher training; involve family

— Trigger identification, coping skills, recovery support (12-step, SMART Recovery, peer recovery coaches)

— Driving safety on MAT — patients on stable doses are generally safe to drive

— MAT continuation ≥12 months strongly correlates with sustained recovery

— Premature MAT discontinuation increases overdose mortality 2–3 fold

— Encourage indefinite maintenance unless patient strongly desires taper, with shared decision-making

— Intensive outpatient programs (IOP), residential treatment, sober living

— Address social determinants: housing, employment, legal

Board pearl: A patient on stable buprenorphine maintenance who requires acute pain management (post-op, trauma) is best served by continuing buprenorphine and adding short-acting opioid + multimodal analgesia (acetaminophen, NSAIDs, regional anesthesia) — discontinuing buprenorphine peri-operatively is no longer recommended in most surgical contexts.

Outpatient follow-up cadence:

Monitoring parameters:

Counseling priorities:

Long-term outcomes:

Rehabilitation / recovery resources:

Ethical, Legal, and Patient Safety Considerations

— All 50 states + DC have some form; shield bystanders from drug possession charges when calling 911 for overdose

— Familiarize patients/families — fear of arrest is a major barrier to calling EMS

— Naloxone Access Laws permit lay administration without medical license

— Acutely intoxicated patients lack capacity for major medical decisions — proceed with emergency care under implied consent

— Once reversed and alert, patients can refuse further treatment if capacity restored — document carefully

— Left-AMA after overdose: assess capacity, offer naloxone Rx anyway, document risk discussion, attempt MAT linkage even if refusing admission

— Child abuse/neglect: any pediatric exposure or overdose in a household with children triggers a CPS report in most states

— Impaired drivers, healthcare workers under influence — variable state requirements

— Death reporting: medical examiner notification for any fatal overdose

— Use person-first, non-stigmatizing language ("person with OUD," not "addict"); document "substance use disorder," not "drug abuse"

— Disparities: Black patients less likely to receive buprenorphine; rural patients face access gaps

— Avoid biased UDS ordering — apply consistent criteria

— 42 CFR Part 2 governs SUD treatment records — stricter than HIPAA; written consent required for disclosure

— Recent reforms (2024) aligned Part 2 more closely with HIPAA for treatment, payment, operations

— High-risk handoff: hospital discharge after overdose — 30-day re-overdose mortality up to 5–10× baseline if no MAT linkage

— Ensure closed-loop referral to MAT provider with confirmed appointment, not just a phone number

— Communicate with PCP within 24–48 h; reconcile opioid Rx in state PDMP (prescription drug monitoring program — check before any opioid Rx)

— Document medical necessity for any opioid Rx; co-prescribe naloxone per CDC and state laws

Step 3 management: Before discharging any overdose survivor, check the state PDMP, document a naloxone Rx with training, schedule a 72-hour MAT visit, and ensure CPS referral if minors live in the home — these are the four pillars of safe transition of care and high-yield Step 3 quality items.

Good Samaritan laws:

Informed consent and capacity:

Mandatory reporting:

Stigma and equity:

Confidentiality:

Transition-of-care safety:

Workplace and DEA issues:

High-Yield Associations and Rapid-Fire Facts

Board pearl: When a stem mentions fentanyl IV push during induction followed by sudden inability to ventilate, the answer is fentanyl-induced chest wall rigidity — give naloxone or rapid neuromuscular blockade, not just more bag squeezing. This is a classic anesthesiology cross-over question.

Triad: CNS depression + respiratory depression + miosis

Most common cause of death: Hypoventilation → hypoxemia → cardiac arrest

Naloxone half-life 30–90 min < most opioid half-lives → re-sedation risk; infusion required for long-acting agents

Methadone QTc: baseline ECG, repeat at steady state and dose escalations; cutoff 450/470/500 ms for action

Meperidine → normeperidine → seizures (especially in renal failure); avoid

Tramadol → seizures + serotonin syndrome

Loperamide megadose → QRS widening, torsades; treat with sodium bicarbonate, magnesium

Fentanyl chest wall rigidity ("wooden chest syndrome") — rapid IV push; treat with naloxone + neuromuscular blockade if intubation needed

Buprenorphine ceiling effect on respiratory depression; rarely fatal except in opioid-naïve children or with co-sedatives

One pill can kill in toddlers: methadone, buprenorphine, oxycodone ER, clonidine, sulfonylureas, calcium channel blockers, TCAs, camphor

Naloxone-resistant "opioid" toxidromes: clonidine, imidazolines, GHB

Body packers vs stuffers: packers = transporters (planned, well-wrapped, large quantity); stuffers = arrest panic (poorly wrapped, smaller doses, sudden toxicity)

NCPE after naloxone: rare, self-limited, supportive care; do NOT withhold future naloxone

Pregnant patients: give naloxone — fetal harm from hypoxia > withdrawal

MAT options: methadone (OTP only), buprenorphine (office), naltrexone XR (after detox)

MAT Act 2023: X-waiver eliminated

Co-prescribe naloxone if: ≥50 MME/day, opioid + benzo, OUD history, prior overdose

CDC opioid prescribing 2022: avoid abrupt taper; individualized goals; non-opioid first-line for chronic non-cancer pain

42 CFR Part 2: SUD records

NOWS (neonatal opioid withdrawal): Finnegan score, morphine/methadone treatment

PDMP: check at every opioid Rx

Number needed to distribute naloxone to save 1 life: ~150–230 kits per averted death (community programs)

Board Question Stem Patterns

Step 3 management: When the question asks "next best step" in opioid overdose, the order is almost always (1) BVM + O₂, (2) naloxone, (3) glucose check, (4) IV access, (5) targeted workup, (6) buprenorphine induction + take-home naloxone before discharge. Memorize this sequence — it answers the majority of stems.

Pattern 1 — Classic ED overdose: "32-yo man brought in unresponsive, RR 6, SpO₂ 78%, pupils 2 mm, BP 100/60." Next step: BVM ventilation + naloxone 0.4–2 mg IV/IM/IN. Wrong answers: intubate first, head CT first, charcoal.

Pattern 2 — Methadone induction: Patient on methadone 80 mg/day starts erythromycin; days later found obtunded with RR 8. Cause: CYP3A4 inhibition ↑ methadone. Management: naloxone (with caution re: withdrawal), discontinue erythromycin, ECG for QTc, consider infusion. Recurrent sedation → naloxone drip + admit.

Pattern 3 — Re-sedation: Heroin OD reversed in ED at 9 AM, patient awake; at 11 AM found unresponsive again. Cause: naloxone half-life < heroin metabolites/fentanyl. Answer: re-bolus + start infusion + admit, not "discharge home."

Pattern 4 — Pediatric methadone ingestion: Toddler found sleepy at grandparent's home. Answer: naloxone 0.1 mg/kg, admit ≥24 h, naloxone infusion likely, CPS referral, lock medications.

Pattern 5 — Post-op opioid + benzo elderly patient: Confusion and bradypnea after hip replacement. Answer: stop benzodiazepine, give low-dose naloxone 0.04 mg IV (avoid precipitated pain crisis), reduce opioid, schedule acetaminophen.

Pattern 6 — Buprenorphine induction: Patient with OUD presents after non-fatal overdose, COWS = 10. Answer: buprenorphine/naloxone induction in the ED, take-home naloxone, warm handoff to MAT clinic within 72 h.

Pattern 7 — Loperamide abuse: Young adult with self-treated OUD, wide QRS, torsades. Answer: sodium bicarbonate, magnesium, naloxone for respiratory effects (won't fix QRS).

Pattern 8 — IDU with fever and new murmur: Tricuspid endocarditis from S. aureus. Answer: blood cultures ×3, empiric vancomycin, TTE → TEE, ID consult, addiction consult, MAT.

Pattern 9 — Pregnant patient overdose: Give naloxone, fetal monitoring, continue or initiate methadone/buprenorphine MAT (not detox).

Pattern 10 — Refractory coma after naloxone: RR normalizes but GCS 5. Answer: head CT, glucose, co-ingestant workup, EEG, not more naloxone.

One-Line Recap

Opioid overdose is a clinical diagnosis of bradypnea + miosis + CNS depression treated immediately with bag-valve-mask oxygenation and titrated naloxone — with every survivor leaving the hospital on take-home naloxone, ED-initiated buprenorphine, and a warm handoff to MAT, because non-fatal overdose is the single highest-risk window for fatal recurrence.

Board pearl: The single highest-yield Step 3 teaching is that every opioid overdose discharge bundle must include naloxone Rx + MAT initiation + closed-loop follow-up — failing to do so is both a clinical and a board-exam error, because the 30-day post-overdose mortality without MAT is among the highest in all of medicine.

Recognize early: RR <12, pinpoint pupils, obtundation — give naloxone empirically alongside BVM and oxygen; titrate to respiratory rate, not consciousness, to avoid precipitated withdrawal in tolerant patients.

Anticipate re-sedation: naloxone's half-life (30–90 min) is shorter than most opioids — observe 1–2 h for short-acting agents and ≥24 h with telemetry for methadone, sustained-release, transdermal patches, and pediatric ingestions; start an infusion at ⅔ of the effective bolus per hour when re-sedation occurs.

Look beyond opioids when naloxone fails: consider clonidine, GHB, anoxic injury, co-ingested benzodiazepines/alcohol, xylazine, or stroke — head CT, glucose, ABG, acetaminophen/salicylate levels, and ECG are mandatory in every intentional overdose.

Convert the crisis into long-term care: prescribe take-home naloxone, initiate buprenorphine in the ED (no X-waiver needed since 2023), link to MAT within 72 hours, screen and treat HIV/HCV, vaccinate, engage harm reduction, and check the PDMP at every opioid prescription — these transitions of care are the heart of Step 3 OUD management.