What is alcohol intoxication?

Alcohol intoxication is a reversible syndrome following recent alcohol consumption, resulting in clinically significant maladaptive behavioural or psychological changes and physical signs related to central nervous system depression. Effects correlate roughly with blood alcohol concentration (BAC) but individual tolerance varies.

Pharmacology & factors affecting intoxication

• Alcohol is a CNS depressant enhancing GABAergic transmission and inhibiting NMDA receptors.
• Factors influencing response: dose, rate of ingestion, tolerance, body weight, sex, food intake, co‑ingested drugs (opioids, benzodiazepines), liver function and genetic metabolism differences.

Clinical features by severity

Immediate clinical assessment

1. Primary survey: Airway, Breathing, Circulation — secure airway if obtunded or GCS ≤8.
2. Check glucose, electrolytes, blood alcohol level (if available), ECG and consider toxicology screen for co‑ingestants.
3. Assess for trauma, head injury, aspiration risk and signs of other medical causes of altered consciousness.
4. Obtain collateral history: estimated drinks, time of last drink, medications, and prior alcohol problems.

Management — practical steps

• Supportive care is the mainstay: airway protection, oxygen, IV fluids, warming, and monitoring vitals.
• Positioning to reduce aspiration risk — left lateral (recovery) position if decreased consciousness but breathing adequately.
• Activated charcoal is not routinely recommended for ethanol alone but may be considered with co‑ingestants when within early window and per toxicology advice.
• Naloxone should be given if opioid co‑ingestion suspected (does not reverse alcohol effects).
• Correct hypoglycaemia promptly; give thiamine if chronic heavy drinking suspected before giving glucose.
• Observe until clinical improvement and safe discharge criteria met; admit if airway compromise, persistent hypoxia, severe co‑morbidities or suspected significant co‑ingestion.

Complications to watch for

• Airway obstruction and aspiration pneumonia.
• Traumatic injuries, intracranial haemorrhage or head injury.
• Hypothermia, electrolyte disturbances, pancreatitis and cardiac arrhythmias.
• Accidental overdose when combined with benzodiazepines, opioids or other sedatives.

Special populations

• Pregnancy: any alcohol can harm the fetus — counsel abstinence and provide obstetric follow‑up.
• Older adults: increased sensitivity, falls risk and interactions with medications.
• Chronic heavy users: may have tolerance — but higher risk for withdrawal when sober.
• Children and adolescents: lower tolerances and higher risk of severe toxicity at lower doses.

Prevention & patient education

• Brief interventions and screening in primary care (AUDIT) to identify risky drinking early.
• Harm reduction: avoid mixing alcohol with opioids/benzodiazepines, set limits, avoid drinking when alone, and arrange safe transport.
• Refer to addiction services for repeated intoxication, dependence or when withdrawal risk exists.