All EMS presentations
ToxicologyClinical presentation

Alcohol intoxication

A streamlined, differential-led presentation for rapid clinical review.

Clinical snapshot

Twenty-second review

  • Alcohol depresses cortical and cerebellar function, impairs airway reflexes and temperature regulation, and can coexist with trauma, hypoglycemia, withdrawal, or toxic co-ingestion.
  • Bradypnea, repeated vomiting, hypothermia, trauma, focal deficit, severe agitation, or failure to improve requires urgent evaluation.
  • Keep hypoglycemia or stroke in the differential; overlapping or concurrent illness remains possible.
  • For alcohol intoxication, trends and combinations of findings are more informative than one isolated vital sign.
Differentials

Compare the clinical patterns

The repeated material is grouped inside each possibility. Open only the condition you need.

Serious3 conditions
Intracranial injuryTime-sensitive high-risk possibility

HPI

Clarify amount and last drink; normal pattern; co-ingestants.

Signs & symptoms

Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.

Focused exam

Assess pupils, skin, bowel sounds, temperature, mental status, respiratory pattern, rhythm, and signs of trauma or concealed co-ingestion; Repeat observations because drug effects may evolve.

Brief pathophysiology

Intracranial injury may cause alcohol intoxication through a time-sensitive process capable of rapid physiological deterioration.

Vital-sign pattern

What the trend may show

Possible pattern

Ventilation is the priority in opioid or sedative toxicity. SpO₂ can look acceptable with supplemental oxygen while dangerous hypoventilation persists.

Respiratory rate (breaths/min)

May fall

Bradypnea, shallow breathing, or apnea indicates ventilatory failure.

Oxygen saturation (SpO₂)

May fall

Desaturation can occur, but SpO₂ does not measure ventilation.

Heart rate (bpm)

Variable

Rate depends on agent, co-ingestants, hypoxia, and baseline.

Blood pressure (mmHg)

May fall

Hypotension can occur in severe toxicity or mixed overdose.

Front-load in the triage report

  • Intracranial injury: Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.
  • Amount and last drink.
  • Normal pattern.
Toxic alcoholTime-sensitive high-risk possibility

HPI

Clarify normal pattern; co-ingestants; trauma/fall/head strike.

Signs & symptoms

Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.

Focused exam

Repeat observations because drug effects may evolve; Assess ventilation, glucose, temperature, pupils, gait when safe, trauma, co-ingestants, and signs of withdrawal or chronic liver disease.

Brief pathophysiology

Toxic alcohol may cause alcohol intoxication through a time-sensitive process capable of rapid physiological deterioration.

Vital-sign pattern

What the trend may show

Possible pattern

Ventilation is the priority in opioid or sedative toxicity. SpO₂ can look acceptable with supplemental oxygen while dangerous hypoventilation persists.

Respiratory rate (breaths/min)

May fall

Bradypnea, shallow breathing, or apnea indicates ventilatory failure.

Oxygen saturation (SpO₂)

May fall

Desaturation can occur, but SpO₂ does not measure ventilation.

Heart rate (bpm)

Variable

Rate depends on agent, co-ingestants, hypoxia, and baseline.

Blood pressure (mmHg)

May fall

Hypotension can occur in severe toxicity or mixed overdose.

Front-load in the triage report

  • Toxic alcohol: Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.
  • Normal pattern.
  • Co-ingestants.
AspirationTime-sensitive high-risk possibility

HPI

Clarify co-ingestants; trauma/fall/head strike; gcs.

Signs & symptoms

Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.

Focused exam

Repeat observations because drug effects may evolve; Assess ventilation, glucose, temperature, pupils, gait when safe, trauma, co-ingestants, and signs of withdrawal or chronic liver disease.

Brief pathophysiology

Aspiration may cause alcohol intoxication through a time-sensitive process capable of rapid physiological deterioration.

Vital-sign pattern

What the trend may show

Possible pattern

Respiratory infection may impair oxygenation and trigger systemic illness. Older or immunocompromised patients may lack fever, so trend all four observations and mental status.

Respiratory rate (breaths/min)

Often rises

Tachypnea can be an early marker of respiratory or systemic illness.

Oxygen saturation (SpO₂)

May fall

Parenchymal disease can impair gas exchange; compare with baseline.

Temperature (°C)

May rise or fall

Fever is common, but normal or low temperature does not exclude serious infection.

Heart rate (bpm)

Often rises

Tachycardia may reflect fever, hypoxia, dehydration, or sepsis.

Front-load in the triage report

  • Aspiration: Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.
  • Co-ingestants.
  • Trauma/fall/head strike.
Common1 condition
Uncomplicated intoxicationCommon presentation pattern

HPI

Clarify amount and last drink; normal pattern; co-ingestants.

Signs & symptoms

Dose-related disinhibition, ataxia, slurred speech, and drowsiness may occur.

Focused exam

Assess pupils, skin, bowel sounds, temperature, mental status, respiratory pattern, rhythm, and signs of trauma or concealed co-ingestion; Repeat observations because drug effects may evolve.

Brief pathophysiology

Uncomplicated intoxication may explain the presenting symptoms through a common clinical mechanism, while serial assessment checks for complications or an alternate cause.

Vital-sign pattern

What the trend may show

Possible pattern

Ventilation is the priority in opioid or sedative toxicity. SpO₂ can look acceptable with supplemental oxygen while dangerous hypoventilation persists.

Respiratory rate (breaths/min)

May fall

Bradypnea, shallow breathing, or apnea indicates ventilatory failure.

Oxygen saturation (SpO₂)

May fall

Desaturation can occur, but SpO₂ does not measure ventilation.

Heart rate (bpm)

Variable

Rate depends on agent, co-ingestants, hypoxia, and baseline.

Blood pressure (mmHg)

May fall

Hypotension can occur in severe toxicity or mixed overdose.

Front-load in the triage report

  • Dose-related disinhibition, ataxia, slurred speech, and drowsiness may occur.
  • Amount and last drink.
  • Normal pattern.
Mimics2 conditions
HypoglycemiaImportant alternative presentation

HPI

Clarify amount and last drink; normal pattern; co-ingestants.

Signs & symptoms

Common mimics that can coexist with alcohol use.

Focused exam

Assess pupils, skin, bowel sounds, temperature, mental status, respiratory pattern, rhythm, and signs of trauma or concealed co-ingestion; Repeat observations because drug effects may evolve.

Brief pathophysiology

Hypoglycemia can resemble alcohol intoxication through overlapping symptoms or referred physiology despite a different primary mechanism.

Vital-sign pattern

What the trend may show

Possible pattern

Confirm low capillary glucose and reassess after treatment. Adrenergic signs may be absent in recurrent hypoglycemia or blunted by medications.

Blood glucose (mmol/L)

< 4.0 mmol/L

BCEHS defines hypoglycemia as blood glucose below 4.0 mmol/L.

Heart rate (bpm)

May rise

Adrenergic activation commonly produces tachycardia, but this is not universal.

Blood pressure (mmHg)

Often preserved

Blood pressure is not a reliable discriminator; hypotension suggests another or additional process.

Temperature (°C)

May fall

Hypothermia can accompany prolonged or severe hypoglycemia.

Front-load in the triage report

  • Common mimics that can coexist with alcohol use.
  • Amount and last drink.
  • Normal pattern.
StrokeImportant alternative presentation

HPI

Clarify normal pattern; co-ingestants; trauma/fall/head strike.

Signs & symptoms

Common mimics that can coexist with alcohol use.

Focused exam

Repeat observations because drug effects may evolve; Assess ventilation, glucose, temperature, pupils, gait when safe, trauma, co-ingestants, and signs of withdrawal or chronic liver disease.

Brief pathophysiology

Stroke can resemble alcohol intoxication through overlapping symptoms or referred physiology despite a different primary mechanism.

Vital-sign pattern

What the trend may show

Possible pattern

Stroke is a clinical diagnosis supported by time course and neurologic findings. Blood pressure and glucose affect eligibility and mimics; normal vitals do not exclude stroke.

Blood pressure (mmHg)

Often elevated

Hypertension is common in acute stroke; hypotension suggests another cause or poor perfusion.

Blood glucose (mmol/L)

Check every patient

Hypoglycemia can mimic focal deficit; hyperglycemia may accompany stress or diabetes.

Heart rate (bpm)

Assess rate / rhythm

An irregular rhythm may suggest atrial fibrillation but is not required.

Oxygen saturation (SpO₂)

Usually preserved

Hypoxemia requires correction and may indicate aspiration or another process.

Front-load in the triage report

  • Common mimics that can coexist with alcohol use.
  • Normal pattern.
  • Co-ingestants.
Red flags

Findings that should escalate concern

  • Bradypnea, repeated vomiting, hypothermia, trauma, focal deficit, severe agitation, or failure to improve requires urgent evaluation.
  • Intracranial injury, toxic alcohol, or aspiration: Trauma, acidosis pattern, visual symptoms, hypoxia, or disproportionate depression.
Related medications

Medication recognition

Gliclazide MRInsulin glargineInsulin aspartGlucagon
Related EMS presentations

Continue the clinical pathway

ToxicologyOverdose / drug poisoningTraumaHead injuryEndocrine/MetabolicHypoglycemiaToxicologyPoisoning / toxic exposureMental HealthBehavioural crisis / agitation
References

Clinical and academic sources

Curated clinical guidance and peer-reviewed evidence supporting this presentation. Current BCEHS guidance, medical direction, and local policy remain authoritative for practice.

BCEHS Handbook — specific CPGs

  1. F01: Altered Levels of ConsciousnessBC Emergency Health Services Handbook

    Official BCEHS clinical practice guidance for altered levels of consciousness.

  2. J01: Approach to Chemical or Toxic ExposuresBC Emergency Health Services Handbook

    Official BCEHS clinical practice guidance for approach to chemical or toxic exposures.

Supporting clinical and academic evidence

  1. CEDIS Presenting Complaint List updateCanadian Association of Emergency Physicians

    Presenting-complaint terminology and categorization context. It does not establish a prehospital “top 100” ranking.

  2. Guidelines for establishing a poison centreWorld Health Organization

    Clinical toxicology context for time-critical poisoning, supportive care, consultation, and poison-centre expertise.

  3. Alcohol intoxication in emergency medicineMedizinische Klinik, Intensivmedizin und Notfallmedizin · 2019

    Assessment of intoxication severity, airway risk, hypoglycemia, trauma, co-ingestion, and withdrawal.