Toxicology & Substance Use · Topic 15 of 17

Alcohol Withdrawal & Delirium Tremens

Toxicology · alcohol withdrawal

Alcohol Withdrawal & Delirium Tremens

Score with CIWA-Ar, treat with symptom-triggered benzodiazepines, give thiamine before glucose — and watch for delirium tremens at 48–96 hours.

Key numbers

DT begins at 48–96 hoursDT at 48–96 h

CIWA-Ar ≥ 10 needs medicationCIWA-Ar ≥ 10 → treat

Thiamine 100 mg IV before glucosethiamine 100 mg IV/IM

01 · The numberDT begins at 48–96 hours

Timeline after the last drink: tremor and autonomic symptoms from 6–24 hours, hallucinosis at 12–24 hours, seizures at 6–48 hours (peak about 24 hours), delirium tremens at 48–96 hours.

02 · Defined byCIWA-Ar ≥ 10 needs medication

Grade severity with the 10-item CIWA-Ar: < 10 mild (supportive care or medication), 10–18 moderate and ≥ 19 severe — moderate and severe withdrawal both need pharmacotherapy.

03 · GiveSymptom-triggered benzodiazepines first-line

Benzodiazepines are first-line; symptom-triggered dosing is preferred over a fixed taper, long-acting agents (diazepam, chlordiazepoxide) are preferred, and severe withdrawal is front-loaded with diazepam or chlordiazepoxide.

Causes & risk factors

Why it happens

Prior seizures or DT predict complicated withdrawalRisk factors for complicated withdrawal: prior withdrawal seizures or delirium, many prior episodes, comorbid illness (especially TBI), age > 65 and long heavy drinking; at-risk patients get preventive benzodiazepines. PAWSS helps predict severity.

Do right now

In this order

First moves

Thiamine 100 mg IV before glucosethiamine 100 mg IV/IM

→

CIWA-Ar ≥ 10 needs medicationCIWA-Ar ≥ 10 → treat

→

Symptom-triggered benzodiazepines first-line

→

DT: ICU, escalating IV benzodiazepine boluses

Why each step

Thiamine 100 mg IV before glucoseGive thiamine 100 mg IV or IM daily for 3–5 days to prevent Wernicke encephalopathy, before any IV dextrose; if Wernicke is suspected, switch to high-dose IV thiamine.

CIWA-Ar ≥ 10 needs medicationGrade severity with the 10-item CIWA-Ar: < 10 mild (supportive care or medication), 10–18 moderate and ≥ 19 severe — moderate and severe withdrawal both need pharmacotherapy.

Symptom-triggered benzodiazepines first-lineBenzodiazepines are first-line; symptom-triggered dosing is preferred over a fixed taper, long-acting agents (diazepam, chlordiazepoxide) are preferred, and severe withdrawal is front-loaded with diazepam or chlordiazepoxide.

DT: ICU, escalating IV benzodiazepine bolusesDelirium tremens is an ICU emergency: give IV benzodiazepines in escalating boluses — eg, diazepam 10 mg IV, doubling the dose every 10–15 minutes until the patient is sedated; there is no maximum dose.

Management

Orders

Phenobarbital: adjunct or benzodiazepine alternativePhenobarbital (experienced clinicians, close monitoring) is an adjunct for severe or benzodiazepine-resistant withdrawal, or monotherapy when benzodiazepines are contraindicated — eg, 10 mg/kg ideal body weight IV; watch for respiratory depression.

Withdrawal seizure: IV lorazepam, not phenytoinAfter a withdrawal seizure give a fast-acting IV benzodiazepine (lorazepam or diazepam), admit with reassessment every 1–2 hours for 6–24 hours, and watch for delirium. Phenytoin does not prevent withdrawal seizures.

Liver disease: lorazepam or oxazepamWith significant liver disease, use a benzodiazepine with less hepatic metabolism — lorazepam or oxazepam (glucuronidated).

Resistant withdrawal: propofol if intubatedFor benzodiazepine-resistant withdrawal in the ICU, add phenobarbital with close monitoring, use propofol in patients already on mechanical ventilation, and consider dexmedetomidine as an adjunct.

Replace magnesium and phosphate when indicatedGive magnesium for hypomagnesemia, arrhythmias or prior withdrawal seizures (not as routine prophylaxis), and replace phosphorus when < 1 mg/dL.

Red flags & don'ts

Avoid harm

Clonidine, dexmedetomidine, beta-blockers: adjuncts only avoidAlpha-2 agonists (clonidine, dexmedetomidine) and beta-blockers may be added for autonomic hyperactivity not controlled by benzodiazepines, but never alone — they do not prevent seizures or delirium.

Antipsychotics only as adjuncts avoidAntipsychotics (eg, haloperidol) may be added only when hallucinations or delirium persist despite benzodiazepines; never use them as monotherapy — they lower the seizure threshold.

Never give alcohol to treat withdrawal avoidOral or IV alcohol should not be used to prevent or treat withdrawal; evidence is also insufficient for baclofen.

The rules

Know these

In delirium use RASS or CAM-ICU, not CIWA-ArDo not use CIWA-Ar once the patient is delirious, because it relies on patient report; monitor with RASS, CAM-ICU or a similar structured scale.

Alcoholic hallucinosis or delirium tremens?

Commonly confused

Onset after last drink	12–24 hours
Consciousness	Clear sensorium
Autonomic signs	Usually absent
Course	Transient; may precede DT

More detail

Reference

Show 6 reference facts

Carbamazepine or gabapentin are alternatives to benzodiazepines in mild to moderate withdrawal and options when benzodiazepines are contraindicated.

Patients receiving repeated high IV doses of lorazepam or diazepam need monitoring for hyponatremia and metabolic acidosis.

Delirium lasting > 72 hours should prompt a search for drug-induced delirium or withdrawal from another GABAergic agent (eg, gabapentin, carisoprodol).

Example symptom-driven front-loading: diazepam 20 mg every hour until CIWA-Ar < 10; once stable (CIWA-Ar < 10 for 24 hours), monitoring can extend to every 4–8 hours.

Marked hyperthermia during delirium tremens is a poor prognostic sign; maintain intravascular volume with IV fluids.

Benzodiazepines cause dependence in alcohol use disorder, so do not continue them after the withdrawal period; avoid physical restraints when possible.

Pearl

Dose to the symptoms, not the clock: symptom-triggered benzodiazepines guided by CIWA-Ar are the standard.

Sources · The ASAM Clinical Practice Guideline on Alcohol Withdrawal Management. J Addict Med 2020;14(3S Suppl 1):1–72 · Merck Manual Professional — Alcohol Toxicity and Withdrawal · Merck Manual Professional — Wernicke Encephalopathy · Starter sheet built from the verified AGACNP fact map (facts reviewed 2026-10-15).