ICU · Toxicology
Acute severe alcohol withdrawal and delirium tremens: CIWA-Ar, benzodiazepines, and Wernicke
Also known as Alcohol withdrawal · Delirium tremens · DTs · CIWA-Ar · Alcohol withdrawal syndrome · AWS
Alcohol withdrawal syndrome (AWS) = symptoms occurring when a chronic alcohol-dependent person STOPS or REDUCES alcohol intake. SPECTRUM: begins 6-24h after last intake (tremor, anxiety, insomnia, nausea, sweating) → hallucinations (12-24h) → seizures (12-48h, up to 15% of patients) → DELIRIUM TREMENS (DTs — typically around 72h after last intake, occurs in 3-5% of withdrawal patients — confusion, hallucinations, autonomic hyperactivity [tachycardia, hypertension, fever, diaphoresis] — mortality as high as 50% without recognition or prompt treatment). PATHOPHYSIOLOGY: chronic alcohol → BRAIN ADAPTS (downregulates inhibitory GABA receptors + upregulates excitatory NMDA receptors) → when alcohol REMOVED → GABA UNDERACTIVE (loss of inhibition) + GLUTAMATE OVERACTIVE (excessive excitation) → hyperexcitable brain → tremor → seizures → DTs. MANAGEMENT: (1) BENZODIAZEPINES (front-line — restore GABA tone — diazepam/lorazepam — symptom-triggered or fixed-schedule). (2) THIAMINE with or before glucose (prevents Wernicke — ICU day-1 supplementation 200-500 mg IV every 8h). (3) ELECTROLYTE/VITAMIN correction (magnesium 64 mg/kg, folate 400-1000 mcg IV). (4) PHENOBARBITAL 10 mg/kg IV (severe or refractory). (5) SUPPORTIVE (exclude sepsis and co-morbidity, ICU for severe DTs).
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- DTs typically around 72 h after last drink (3-5% of withdrawal patients) — confusion + hallucinations + autonomic hyperactivity — mortality as high as 50% without prompt treatment
- BENZODIAZEPINES are first-line (restore GABA effect) — CIWA-Ar-guided symptom-triggered dosing
- GIVE THIAMINE WITH OR BEFORE GLUCOSE (concurrent thiamine prevents Wernicke encephalopathy and subsequent Korsakoff syndrome)
- Withdrawal seizures: 12-48 h after last drink (up to 15%) — benzodiazepines reduce seizures (RR 0.16 vs placebo); non-benzodiazepine anticonvulsants do not prevent them
- Correct Mg + K + phosphate (all depleted — worsen seizures/arrhythmia)
| Stage | Timing | Symptoms | Management |
|---|---|---|---|
| Minor withdrawal | 6-24h (onset) | Tremor, agitation, anxiety, insomnia, nausea, sweating, vomiting, hallucinations, tachycardia, hypertension | Benzodiazepine, fixed-dose or symptom-triggered; give at symptom onset and continue until symptoms subside; thiamine; electrolytes[8] |
| Alcoholic hallucinosis | 12-24h (2-8%) | Hallucinations with the withdrawal syndrome | Benzodiazepine; supportive care[7] |
| Withdrawal seizures | 12-48h (up to 15%) | Generalised seizures during withdrawal | Benzodiazepines — seizures RR 0.16 vs placebo; carbamazepine, oxcarbazepine, valproate, gabapentin have less abuse potential but do NOT prevent withdrawal seizures[6][8] |
| Delirium tremens (DTs) | typically ~72h (3-5%) | Potentially fatal encephalopathy: delirium with agitation, hallucinations, life-threatening autonomic dysfunction | ICU with continuous monitoring; benzodiazepines are the mainstay (diazepam or lorazepam); phenobarbital 10 mg/kg IV for refractory; exclude and treat underlying co-morbid illness incl. infection; severe withdrawal may progress to intubation and mechanical ventilation[7][3][4] |
- ASSESS SEVERITY AND PREDICT RISK (CIWA-Ar + PAWSS) — (a) CIWA-Ar (Clinical Institute Withdrawal Assessment for Alcohol, Revised): a validated shortened 10-item scale for clinical quantitation of withdrawal severity — scored repeatedly at the bedside; a benzodiazepine dose is given when the score exceeds the local protocol threshold and the score is repeated after dosing.[1] (b) SYMPTOM-TRIGGERED DOSING: individualized, scale-guided therapy gave a median treatment duration of 9 vs 68 hours and total chlordiazepoxide of 100 vs 425 mg versus fixed-schedule, with equal efficacy and no difference in seizures or delirium tremens (Saitz, JAMA 1994).[2] (c) HIGH-INTENSITY-CARE SIGNAL: in a multicentre cohort of 8742 hospitalized adults the odds of progressing to intermediate care or ICU rose above 1.0 once the CIWA-Ar reached 24 — but sensitivity at that cut-point was only 0.12, so treat the trend and the patient, not a single number.[13] (d) PREDICT, do not just react: PAWSS (Prediction of Alcohol Withdrawal Severity Scale) — 10 items derived from 233 predictive articles — identifies patients at risk of COMPLICATED withdrawal (hallucinosis, withdrawal seizures, DTs) BEFORE symptoms appear; in the pilot (68 medically ill inpatients) sensitivity, specificity, PPV and NPV were all 100% at the threshold score of 4, so a PAWSS of 4 or above should prompt escalated monitoring and prophylaxis.[14] (e) TIMING: symptoms typically manifest within 8 hours of cessation, peak over 1 to 3 days, and can extend for up to 2 weeks; the syndrome begins 6 to 24 hours after the last intake.[7][8] (f) EXCLUDE mimics: electrolyte abnormalities, trauma in the intoxicated patient, hypoglycaemia, sepsis — work-up includes CBC, metabolic panel, magnesium, and CT brain where indicated.[7]
- BENZODIAZEPINE (FIRST-LINE) — (a) MECHANISM: chronic heavy alcohol downregulates CNS inhibitory GABA receptors and upregulates excitatory NMDA receptors; abrupt cessation leaves excitation unopposed. Benzodiazepines restore GABAergic inhibitory tone and calm the hyperexcitable brain.[7] (b) EVIDENCE: versus placebo, benzodiazepines reduced seizures RR 0.16 (95% CI 0.04-0.69; Cochrane, 64 trials); in the 149-trial network meta-analysis, fixed-schedule diazepam (OR 0.16, 0.04-0.59), lorazepam (OR 0.19, 0.08-0.45) and chlordiazepoxide (OR 0.21, 0.08-0.53) each beat placebo for incident withdrawal seizures — and only fixed-schedule diazepam reduced incident delirium tremens (OR 0.19, 0.05-0.76).[6][9] (c) AGENTS: benzodiazepines are the mainstay; diazepam and lorazepam are the preferred agents depending on treatment regime and clinical context (e.g. hepatic impairment); no single agent has proven clearly superior.[4][6] (d) DOSING STRATEGY: fixed-dose or symptom-triggered schedules are both recommended — give medication at the onset of symptoms and continue until symptoms subside; symptom-triggered (scale-guided) dosing is favoured because it cuts total dose and treatment duration without losing efficacy.[8][2]
- THIAMINE (WITH OR BEFORE GLUCOSE) — (a) WHY: manage hypoglycaemia with CONCURRENT administration of thiamine to prevent Wernicke encephalopathy and subsequent Korsakoff syndrome — glucose given to a thiamine-depleted drinker can precipitate acute depletion.[7] (b) ICU DOSING: for chronic alcohol use disorder admitted to the ICU, suggested day-1 supplementation is thiamine 200-500 mg IV every 8 hours (with magnesium sulfate and folate — below); abandon the reflexive standard banana bag, whose thiamine content likely fails to optimize CNS delivery.[10] (c) WHAT DOSE IS OPTIMAL? The only dose-ranging RCT found NO clear benefit of high-dose over intermediate or lower thiamine: at-risk drinkers received 100 mg daily vs 100 mg TDS vs 300 mg TDS for 3 days (N=393) and symptomatic Wernicke patients 100 vs 300 vs 500 mg TDS for 5 days (N=127) with no significant differences in cognitive or neurological outcomes — choose patient-specific dosing and correct magnesium and other B-vitamin deficits.[11] (d) The Cochrane review confirms thiamine has been the treatment of choice for over 50 years but RCT evidence is INSUFFICIENT to determine dose, frequency, route or duration — do not present any single regimen as proven.[5] (e) NOTE: if alcoholic ketoacidosis is suspected, dextrose-containing fluids are recommended OVER normal saline (with thiamine on board).[10]
- ELECTROLYTE AND VITAMIN CORRECTION — (a) MAGNESIUM and folate may merit supplementation in these patients: the evidence-based ICU day-1 formula pairs thiamine 200-500 mg IV q8h with magnesium sulfate 64 mg/kg IV (approximately 4-5 g for most adults) and folate 400-1000 mcg IV.[10] (b) Magnesium and other B-vitamin deficiencies should be considered and corrected when treating Wernicke-Korsakoff syndrome — biochemical cofactors matter as much as the thiamine dose.[11] (c) There is NO available evidence supporting prescription of a multivitamin in this setting — replace what is deficient, not the kitchen sink.[10] (d) Check the full electrolyte panel (sodium, potassium, phosphate, glucose) — alcohol-associated deficiencies worsen withdrawal and its complications, and refeeding risk rises once nutrition starts.
- PHENOBARBITAL (SEVERE OR BENZODIAZEPINE-REFRACTORY) + ALTERNATIVES — (a) EVIDENCE (RCT): a single IV phenobarbital dose of 10 mg/kg (in 100 mL normal saline) added to a standardized symptom-guided lorazepam-based protocol reduced ICU admission to 8% vs 25% with placebo (95% CI of difference 4-32), with no difference in adverse events.[3] (b) IMPLEMENTATION: a hospital-wide weight-based IV loading order set (10 or 15 mg/kg) across ED, acute care and ICU was associated with faster symptom resolution (4.2-5.0-point lower daily maximum CIWA-Ar at 24-96 h), 30.1 h shorter treatment duration and 2.2 days shorter time to discharge, with no difference in intubation, restraint or mortality outcomes.[15] (c) REFRACTORY DTs: phenobarbital, propofol and dexmedetomidine are the options when benzodiazepines fail; barbiturates, ketamine and propofol are alternatives or adjuncts in severe withdrawal, which may progress to intubation and mechanical ventilation.[4][7]
- SUPPORTIVE CARE, CO-MORBIDITY AND DISPOSITION — (a) WORK-UP: complete blood count, complete metabolic panel, magnesium level, and CT brain where indicated; actively look for the broad differential — electrolyte abnormalities, trauma in the intoxicated patient, infection, hypoglycaemia.[7] (b) CO-MORBIDITY: assessment of DT must include screening for underlying medical co-morbidities — liver disease is very common in DT patients and complicates presentation, treatment choice and outcome; never attribute fever or deterioration to withdrawal alone.[4] (c) SUPPORTIVE: quiet environment, treat agitation pharmacologically, physical restraints only as a last resort; manage hypoglycaemia with concurrent thiamine.[7] (d) DISPOSITION: severe withdrawal warrants ICU-level care after critical-care consultation; patients needing high-intensity care cannot be reliably identified from a single CIWA-Ar number — serial assessment plus medication exposure (lorazepam-equivalent dose above 15 mg in 24 h also signalled risk in the 8742-patient cohort) guides escalation.[13] (e) BEFORE DISCHARGE: effective treatment of the withdrawal is only the initial step — long-term success depends on facilitating the patient's entry into ongoing treatment (addiction medicine liaison).[8]
SAQ — Delirium tremens in the ICU
10 minutes · 10 marks
A 49-year-old man with chronic alcohol dependence (1 bottle of spirits/day) is admitted 60 hours after his last drink following a seizure at home. He is grossly tremulous, agitated, hallucinating (seeing insects on the wall), diaphoretic, HR 142, BP 184/105, temp 39.1°C, RR 30, GCS 13, with Mg²⁺ 0.45 mmol/L, K⁺ 2.9 mmol/L, phosphate 0.5 mmol/L, CK 4,200 U/L, and a CIWA-Ar of 27. His wife gave him a dextrose-containing IV fluid in the ambulance.
SAQ — Wernicke encephalopathy and refractory withdrawal
10 minutes · 10 marks
A 56-year-old malnourished woman with alcohol cirrhosis (Child-Pugh B) is admitted in severe AWS. Despite 80 mg of IV diazepam in 4 h she remains severely agitated, tremulous and has developed nystagmus, lateral rectus palsy and a wide-based gait when she tries to stand. The team has just prescribed a 5% dextrose infusion for rehydration.
Clinical pearls
References15ShowHide
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- [2]Saitz R, Mayo-Smith MF, Roberts MS, et al. Individualized treatment for alcohol withdrawal. A randomized double-blind controlled trial. JAMA, 1994.PMID 8046805
- [3]Rosenson J, Clements C, Simon B, et al. Phenobarbital for acute alcohol withdrawal: a prospective randomized double-blind placebo-controlled study. J Emerg Med, 2013.PMID 22999778
- [4]Grover S, Ghosh A Delirium Tremens: Assessment and Management. J Clin Exp Hepatol, 2018.PMID 30564004
- [5]Day E, Bentham PW, Callaghan R, et al. Thiamine for prevention and treatment of Wernicke-Korsakoff Syndrome in people who abuse alcohol. Cochrane Database Syst Rev, 2013.PMID 23818100
- [6]Amato L, Minozzi S, Vecchi S, et al. Benzodiazepines for alcohol withdrawal. Cochrane Database Syst Rev, 2010.PMID 20238336
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- [8]Muncie HL Jr, Yasinian Y, Oge' L. Outpatient management of alcohol withdrawal syndrome. Am Fam Physician, 2013.PMID 24364635
- [9]Bahji A, Bach P, Danilewitz M, et al. Comparative efficacy and safety of pharmacotherapies for alcohol withdrawal: a systematic review and network meta-analysis. Addiction, 2022.PMID 35194860
- [10]Flannery AH, Adkins DA, Cook AM. Unpeeling the Evidence for the Banana Bag: Evidence-Based Recommendations for the Management of Alcohol-Associated Vitamin and Electrolyte Deficiencies in the ICU. Crit Care Med, 2016.PMID 27002274
- [11]Dingwall KM, Delima JF, Binks P, et al. What is the optimum thiamine dose to treat or prevent Wernicke's encephalopathy or Wernicke-Korsakoff syndrome? Results of a randomized controlled trial. Alcohol Clin Exp Res, 2022.PMID 35428992
- [12]Harper CG, Giles M, Finlay-Jones R. Clinical signs in the Wernicke-Korsakoff complex: a retrospective analysis of 131 cases diagnosed at necropsy. J Neurol Neurosurg Psychiatry, 1986.PMID 3701343
- [13]To DC, Steel TL, Carey KA, et al. Alcohol Withdrawal Severity Measures for Identifying Patients Requiring High-Intensity Care. Crit Care Explor, 2024.PMID 38505174
- [14]Maldonado JR, Sher Y, Ashouri JF, et al. The "Prediction of Alcohol Withdrawal Severity Scale" (PAWSS): systematic literature review and pilot study of a new scale for the prediction of complicated alcohol withdrawal syndrome. Alcohol, 2014.PMID 24657098
- [15]Wolpaw BJ, Oren H, Quinnan-Hostein L, et al. Hospital-Wide Implementation, Clinical Outcomes, and Safety of Phenobarbital for Alcohol Withdrawal. JAMA Netw Open, 2025.PMID 40853658