1. History
- Type, quantity, and timing of alcohol consumed; type of beverage (beer, wine, spirits, unknown/adulterated)
- Rate of consumption (binge vs. sustained), time of last drink, and time of symptom onset
- Tolerance history: chronic heavy drinker vs. naive drinker — nontolerant individuals are at significantly higher risk of respiratory depression at lower BAC levels [1]
- Co-ingestions: other drugs, medications, illicit substances, or possible toxic alcohols (methanol, ethylene glycol) [2]
- Intent: accidental, recreational, or intentional (suicidal ideation/attempt)
- Associated events: falls, trauma, motor vehicle collision, assault, aspiration, exposure to cold
- Preceding symptoms: vomiting, abdominal pain, visual changes (raises concern for toxic alcohol), chest pain
- Last oral intake (food), hydration status
2. Alarm Features
- Respiratory depression (RR <12, SpO₂ <92%), apnea, or loss of gag reflex
- GCS ≤8 or rapidly declining mental status — intubation threshold
- BAC >300–400 mg/dL in nontolerant individuals — risk of coma and death [1]
- Hypotension (SBP <90), severe hypothermia (<35°C) [3-4]
- Seizures (consider toxic alcohol, withdrawal, or structural pathology) [5]
- Focal neurological deficits — must rule out intracranial hemorrhage or stroke
- Persistent altered mental status disproportionate to BAC or failure to improve as BAC falls
- Visual complaints (methanol), flank pain/anuria (ethylene glycol) [2]
- Signs of trauma: periorbital ecchymosis, Battle sign, hemotympanum, CSF rhinorrhea/otorrhea
- Suicidal ideation or self-harm
3. Medications
Relevant contributors/interactions
- CNS depressants (benzodiazepines, opioids, barbiturates, Z-drugs, gabapentinoids) — synergistic respiratory depression and sedation [6]
- Acetaminophen — increased hepatotoxicity risk with chronic alcohol use [6]
- Warfarin — alcohol is among the strongest risk factors for major bleeding on warfarin [6]
- Metformin — risk of lactic acidosis in dehydrated, intoxicated patients
- MAOIs — tyramine in beer/wine can cause hypertensive crisis [6]
- Disulfiram, metronidazole, certain cephalosporins (cefotetan, ceftriaxone) — disulfiram-like reactions [6]
Contraindicated in acute intoxication
- Avoid additional sedatives/hypnotics unless managing agitation with clear indication
- Do not give disulfiram or naltrexone during acute intoxication
- Avoid activated charcoal (ethanol is rapidly absorbed; no benefit, aspiration risk)
Treatments
- Thiamine 100 mg IV before glucose administration (prevent Wernicke encephalopathy) [7]
- Dextrose (D50) for documented hypoglycemia
- IV crystalloid for dehydration/hypotension
- Ondansetron or metoclopramide for nausea/vomiting
- Metadoxine (available in some countries) accelerates ethanol metabolism [8-9]
4. Diet
- NPO if altered mental status or risk of aspiration
- Correct hypoglycemia with IV dextrose; chronic drinkers have depleted glycogen stores [10]
- Rehydrate with oral fluids once alert and tolerating PO
- Long-term: nutritional counseling for chronic drinkers — thiamine, folate, and multivitamin supplementation
- Chronic alcohol users are frequently malnourished with deficiencies in B vitamins, magnesium, zinc, and phosphate
5. Review of Systems
- Neuro: headache, visual changes, seizures, focal weakness, confusion, memory gaps/blackouts
- GI: nausea, vomiting, hematemesis, abdominal pain, diarrhea
- Cardiac: palpitations, chest pain (holiday heart, cardiomyopathy)
- Pulmonary: cough, dyspnea, aspiration symptoms
- Psych: suicidal ideation, depression, anxiety, hallucinations
- MSK/Trauma: pain anywhere suggesting occult injury
- GU: urinary retention (common in intoxicated patients)
6. Collateral History and Family History
- Collateral is critical — intoxicated patients are often unreliable historians
- Bystanders/EMS: witnessed events, substances available, trauma, duration of unconsciousness, last known normal
- Family/friends: baseline drinking pattern, prior ED visits for intoxication, history of withdrawal seizures or delirium tremens [11]
- Family history of alcohol use disorder, psychiatric illness
- Social context: housing status, employment, access to follow-up, domestic violence screening
7. Risk Factors
- Chronic alcohol use disorder — tolerance masks severity; higher risk of withdrawal on the back end
- Young age/adolescents — immature hepatic alcohol dehydrogenase, more susceptible to toxic effects [12]
- Elderly — decreased hepatic metabolism, increased sensitivity, higher fall risk [4]
- Low body weight, female sex (lower volume of distribution, less gastric ADH)
- Empty stomach (faster absorption)
- Polysubstance use (opioids, benzodiazepines, stimulants)
- Psychiatric comorbidities (depression, PTSD) — increased risk of intentional ingestion
- Homelessness, social isolation
8. Differential Diagnosis
Cannot-miss diagnoses
- Toxic alcohol ingestion (methanol, ethylene glycol, isopropanol) — check osmolal gap, anion gap, visual symptoms, crystalluria [2]
- Traumatic intracranial hemorrhage (subdural, epidural, SAH) — intoxicated patients fall frequently; 1 per 1,000 ED encounters for intoxication had intracranial hemorrhage [3]
- Hypoglycemia — aOR 9.2 for critical illness in intoxicated patients [3]
- Sepsis/meningitis — fever + AMS in an intoxicated patient must not be attributed to alcohol alone
- Opioid or sedative-hypnotic co-ingestion — respiratory depression out of proportion to BAC
Other important differentials
- Diabetic ketoacidosis or alcoholic ketoacidosis [10]
- Hepatic encephalopathy in known cirrhotics
- Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia)
- Postictal state or status epilepticus
- Carbon monoxide poisoning
- Hyponatremia or other electrolyte derangements
- Alcohol withdrawal — severe intoxication can mimic withdrawal with confusion, tachycardia, and diaphoresis [5]
9. Past Medical History
- Prior episodes of intoxication, ED visits, or ICU admissions
- History of alcohol withdrawal seizures or delirium tremens — critical for anticipating withdrawal [11]
- Chronic liver disease, cirrhosis, varices, pancreatitis
- Psychiatric history: depression, bipolar disorder, prior suicide attempts
- Traumatic brain injury (common in chronic drinkers)
- Seizure disorder (lower threshold with alcohol)
- Medication list (especially sedatives, anticoagulants, acetaminophen)
- Surgical history (e.g., gastric bypass — altered absorption kinetics)
10. Physical Exam
Vital signs
- Hypothermiahypotensiontachycardiahypoxiafever[3]
Focused exam
- HEENT: pupil size/reactivity (opioid co-ingestion → miosis; toxic alcohol → mydriasis), nystagmus (DSM-5 criterion), scleral icterus, breath odor (fruity = ketoacidosis; solvent-like = isopropanol), oral trauma, hemotympanum [1]
- Neuro: GCS, speech (slurred), gait (ataxic), coordination, cerebellar signs, focal deficits (must rule out stroke/bleed), deep tendon reflexes
- Skin: lacerations, bruising, signs of trauma, needle tracks, spider angiomata, palmar erythema, jaundice
- Abdomen: tenderness (pancreatitis, liver disease, GI bleed), hepatomegaly, ascites
- Chest: auscultation for aspiration (crackles, rhonchi)
- MSK: palpate C-spine, extremities for occult fractures
- Rectal (if indicated): melena, hematochezia
11. Lab Studies
- Blood alcohol concentration (BAC) — confirms diagnosis, useful for clinical-BAC correlation and medicolegal purposes [1][8]
- Point-of-care glucose — hypoglycemia is common and immediately treatable (aOR 9.2 for critical illness) [3]
- BMP/CMP: electrolytes (hypokalemia in 12%, hypocalcemia in 14% of adolescents), renal function, glucose, bicarbonate [13]
- Serum osmolality (calculated vs. measured) → osmolal gap if toxic alcohol suspected [2][14]
- Anion gap — elevated in toxic alcohols, AKA, DKA, lactic acidosis
- VBG/ABG — pH, lactate (hyperlactatemia in ~61% of intoxicated adolescents) [13]
- Hepatic panel — AST, ALT, bilirubin (baseline liver function, acute hepatitis)
- Lipase — if abdominal pain (alcoholic pancreatitis)
- CBC — infection, macrocytosis (chronic use), thrombocytopenia
- Urine drug screen — co-ingestions
- Serum ketones (beta-hydroxybutyrate) — if AKA suspected [10]
- Magnesium, phosphate — frequently depleted in chronic drinkers [7]
- Coagulation studies — if liver disease or bleeding
- Pregnancy test — all women of childbearing age
12. Imaging
- CT head without contrast — indicated for:
- Focal neurological deficits
- GCS disproportionate to BAC or failure to improve
- Evidence of head trauma, coagulopathy
- Seizure (especially new-onset) [5]
- Intracranial hemorrhage occurred in 1/1,000 intoxicated ED patients initially assessed as uncomplicated [3]
- C-spine imaging — if mechanism of injury or unable to clinically clear
- Chest X-ray — if concern for aspiration pneumonia, respiratory distress
- CT abdomen/pelvis — if significant abdominal pain (pancreatitis, perforation, trauma)
- Imaging is not routinely necessary for uncomplicated, mild-moderate intoxication with improving mental status and no trauma
13. Special Tests
- Osmolal gap calculation: Measured osmolality − Calculated osmolality (2×Na + Glucose/18 + BUN/2.8 + EtOH/3.7). Gap >10 mOsm/kg raises concern for toxic alcohol [14-15]
- CAGE, AUDIT, or AUDIT-C screening for underlying alcohol use disorder once patient is sober [8]
- CIWA-Ar — monitor for emerging withdrawal as BAC falls [7][16]
- PAWSS (Prediction of Alcohol Withdrawal Severity Scale) — for withdrawal risk stratification [7]
- Urine calcium oxalate crystals — ethylene glycol poisoning [2]
- Serum methanol/ethylene glycol levels — if toxic alcohol suspected (may require send-out) [2]
14. ECG
- Obtain ECG if:
- Tachycardia, bradycardia, or irregular rhythm
- Chest pain or syncope
- Co-ingestion suspected (tricyclics → wide QRS; opioids; stimulants)
- Known cardiac history
- Findings to watch for:
- QTc prolongation (alcohol, co-ingestants, electrolyte abnormalities)
- Atrial fibrillation ("holiday heart syndrome")
- ST changes (demand ischemia, Takotsubo)
- Conduction delays (co-ingestion with cardiotoxic drugs)
- Not routinely required for uncomplicated intoxication in young, healthy patients
15. Assessment
Severity stratification by BAC (nontolerant individuals): [1]
- Mild (50–150 mg/dL): euphoria, impaired judgment, mild incoordination
- Moderate (150–250 mg/dL): slurred speech, ataxia, nausea, diplopia, nystagmus
- Severe (250–400 mg/dL): stupor, marked incoordination, vomiting, hypothermia, hypotension
- Life-threatening (>400 mg/dL): coma, respiratory depression, cardiovascular collapse, death
Tolerant individuals may appear minimally symptomatic at levels that would be lethal in naive drinkers. Clinical-BAC discordance should prompt a search for co-ingestions or alternative diagnoses.
Complications to consider
- Aspiration pneumonia/pneumonitis
- Rhabdomyolysis (prolonged immobilization)
- Compartment syndrome
- Alcohol withdrawal (begins 6–24 hours after last drink in dependent patients) [11]
- Wernicke encephalopathy
- Alcoholic ketoacidosis [10]
- GI bleeding (Mallory-Weiss tear, variceal bleed)
16. Treatment Plan
Initial stabilization
- ABCs: Protect airway — lateral decubitus positioning; intubate if GCS ≤8 or loss of protective reflexes
- Continuous pulse oximetry and cardiac monitoring for severe intoxication
- IV access, fluid resuscitation with NS or LR for dehydration/hypotension [12]
Medications
- Thiamine 100 mg IV before any glucose-containing fluids [7][17]
- Dextrose (D50W 50 mL IV or D10 infusion) for confirmed hypoglycemia
- Electrolyte repletion: magnesium (2 g IV MgSO₄), potassium, phosphate as needed
- Antiemetics: ondansetron 4 mg IV for persistent vomiting
- Naloxone 0.4–2 mg IV if opioid co-ingestion suspected (respiratory depression, miosis)
- Fomepizole 15 mg/kg IV loading dose if toxic alcohol co-ingestion suspected [2]
Agitation management
- De-escalation first; avoid physical restraints when possible
- If pharmacologic sedation needed: haloperidol 5 mg IM or droperidol 2.5–5 mg IM
- Avoid benzodiazepines during active intoxication unless treating concurrent withdrawal — risk of additive respiratory depression [6]
Supportive care
- Serial reassessments of mental status, vitals, and GCS
- Foley catheter if unable to void and prolonged observation anticipated
- Warm blankets/active rewarming for hypothermia
17. Disposition
Discharge criteria
- Clinically sober: ambulatory, oriented, able to tolerate PO, stable vitals
- BAC trending down with clinical improvement
- No evidence of co-ingestion, trauma, or medical comorbidity requiring further workup
- Not at risk for self-harm (psychiatric clearance if intentional ingestion)
- Responsible adult available or safe disposition plan [5][12]
Observation (ED observation unit)
- Most patients with uncomplicated intoxication can be managed in an ED observation unit with clinical course typically completed within 24 hours [12]
- Monitor for emerging alcohol withdrawal as BAC falls [5]
Admission criteria
- Persistent hemodynamic instability, respiratory compromise, or need for intubation
- Significant co-ingestion or toxic alcohol poisoning
- Intracranial pathology or significant traumatic injury
- Severe metabolic derangement (AKA, refractory hypoglycemia)
- Active suicidal ideation or psychiatric emergency
- Anticipated severe alcohol withdrawal (history of seizures, DTs) [5][18]
Specialist consultation triggers
- Toxicology: toxic alcohol ingestion, unknown co-ingestion
- Neurosurgery: intracranial hemorrhage
- GI: variceal bleeding, severe pancreatitis
- Psychiatry: suicidal ideation, intentional ingestion
- Addiction medicine: recurrent presentations, AUD screening [8]
18. Follow Up / Return Precautions
Follow-up
- PCP follow-up within 1–2 days if discharged with concern for withdrawal risk
- Screen for alcohol use disorder using AUDIT/CAGE once sober — acute intoxication is a sentinel event for underlying AUD [8]
- Brief intervention and referral to addiction services (SBIRT model)
- Outpatient thiamine and multivitamin supplementation for chronic drinkers
Return precautions — instruct patient and responsible party:
- Return immediately for: recurrent vomiting (especially with blood), worsening confusion or inability to arouse, seizures, fever, severe headache, visual changes, chest pain, or difficulty breathing
- Expected course: symptoms should steadily improve as BAC falls (~15–20 mg/dL per hour) [1]
- Do not drive, operate machinery, or make important decisions until fully sober
- Avoid acetaminophen and sedating medications during recovery
Counseling
- Discuss risks of binge drinking, aspiration, trauma, and death
- Provide resources for alcohol cessation (AA, SMART Recovery, addiction hotline)
- If recurrent presentations, strongly recommend formal AUD treatment referral [8]
Images
References
1. Diagnostic and Statistical Manual of Mental Disorders. — Dilip V. Jeste, Jeffrey A. Lieberman, David Fassler, et al American Psychiatric Association (2022). 2022.
2. Toxic Alcohols. — Kraut JA, Mullins ME. The New England Journal of Medicine. 2018.
3. Unsuspected Critical Illness Among Emergency Department Patients Presenting for Acute Alcohol Intoxication. — Klein LR, Cole JB, Driver BE, et al. Annals of Emergency Medicine. 2018.
4. Severe Hypotension and Hypothermia Caused by Acute Ethanol Toxicity. — Wilson E, Waring WS. Emergency Medicine Journal : EMJ. 2007.
5. Clinical Practice Guideline on Alcohol Withdrawal Management. — Anika Alvanzo MD MS DFASAM FACP, Kurt Kleinschmidt MD FASAM, Julie A. Kmiec DO FASAM, et al American Society of Addiction Medicine (2020). 2020.
6. Alcohol-Medication Interactions: Potentially Dangerous Mixes. — Aaron White PhD, Raye Z. Litten PhD, Laura E. Kwako PhD, Maureen B. Gardner National Institute on Alcohol Abuse and Alcoholism (2025). 2025.
7. Managing Selected Chronic Conditions in Hospitalized Patients. — Gauer RL, Abellada A, Stewart M, Kozloski R. American Family Physician. 2024.
8. Identification and Management of Acute Alcohol Intoxication. — Mirijello A, Sestito L, Antonelli M, Gasbarrini A, Addolorato G. European Journal of Internal Medicine. 2023.
9. Acute Alcohol Intoxication. — Vonghia L, Leggio L, Ferrulli A, et al. European Journal of Internal Medicine. 2008.
10. Alcoholic Ketoacidosis: Etiologies, Evaluation, and Management. — Long B, Lentz S, Gottlieb M. The Journal of Emergency Medicine. 2021.
11. Will This Hospitalized Patient Develop Severe Alcohol Withdrawal Syndrome?The Rational Clinical Examination Systematic Review. — Wood E, Albarqouni L, Tkachuk S, et al. The Journal of the American Medical Association. 2018.
12. Role of First Aid in the Management of Acute Alcohol Intoxication: A Narrative Review. — Piccioni A, Tarli C, Cardone S, et al. European Review for Medical and Pharmacological Sciences. 2020.
13. Acute Alcohol Intoxication-Related Metabolic and Biochemical Disturbances in Adolescents: A Matched Case-Control Study. — Hanalioglu D, Ozkocer C, Can Ozalp E, et al. Clinical Pediatrics. 2024.
14. Physiological Approach to Assessment of Acid–Base Disturbances. — Berend K, de Vries AP, Gans RO. The New England Journal of Medicine. 2014.
15. Initial Management of Ingestions of Toxic Substances. — Kulig K. The New England Journal of Medicine. 1992.
16. Management of Alcohol Use Disorder: A Gastroenterology and Hepatology-Focused Perspective. — Díaz LA, König D, Weber S, et al. The Lancet. Gastroenterology & Hepatology. 2025.
17. Identification and Treatment of Alcohol Use Disorder. — Haber PS. The New England Journal of Medicine. 2025.
18. Guidelines for Managing Substance Withdrawal in Jails. — Jeffrey Alvarez MD CCHP, Andrew F. Angelino MD, Oscar Aviles CPM CJM CCE CCHP, et al American Society of Addiction Medicine (2023). 2023.