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Knowledge Exchange > Primary Care > Toolkits > Addiction Toolkit > Alcohol > What are the serious complications of alcohol withdrawal?

Dealing with alcohol problems
What are the serious complications of alcohol withdrawal?

© 2010 CAMH and St. Joseph’s Health Centre, Toronto

Alcohol withdrawal can include serious complications such as seizures, delirium tremens, hallucinations without delirium, electrolyte disturbances, and arrhythmias. Wernicke-Korsakoff syndrome is not caused by withdrawal but can accompany it. Table 1 outlines the features and management of these complications.

Alcohol withdrawal may also be complicated by other acute medical conditions such as hepatic encephalopathy, depression and surgery. Their features and management are detailed in Table 2.

Table 1: Management of the complications of alcohol withdrawal

(Download a PDF of Table 1)


Clinical features




The most common complication

Grand mal, non-focal, brief

2–3 days after last drink

Prevention: Diazepam 20 mg po q 1–2 H for at least 3 doses even if Clinical Institute Withdrawal Assessment of Alcohol Scale, Revised (CIWA-Ar) score < 10

Phenytoin ineffective

Investigate if: 1st seizure in a patient over 40 years old; focal features; outside time frame; head trauma

Delirium tremens


Starts 3–5 days after last drink, lasts several days

More common with surgery or acute medical illness

Extreme disorientation to person, place and time

Vivid hallucinations, often visual and believed by patient

Paranoid delusions, agitation

Sometimes fever, sweating, tremor, vomiting, hypertension, tachycardia

Sometimes no autonomic sx

Often worse at night

Sudden death can occur from arrhythmias due to hypokalemia and catecholamine excess

May be prevented by early and consistent use of diazepam (often several hundred mg required)

IM haloperidol for severe agitation

Atypical antipsychotics for delirium

Aggressive fluid and electrolyte replacement

Often needs sitter at night

Form 1 if confused and tries to leave

Avoid restraints if possible

Admit to ICU if severe autonomic hyperactivity not responding to diazepam

Intubation, propofol, IV lorazepam


Hallucinations without delirium


Usually tactile but may be auditory or visual

Patient is oriented, knows hallucinations are unreal

Responds to low-dose antipsychotics

If patient in acute withdrawal, give at least 3 doses of diazepam (antipsychotics lower seizure threshold)

Electrolyte disturbances

Low potassium and magnesium common

May trigger arrhythmias

Baseline and daily monitoring and replacement until withdrawal resolves



Any supraventricular or ventricular tacchyarrhythmia possible

More likely with low potassium or magnesium, cardiomyopathy, elderly patients, severe withdrawal, cocaine use

Cardiac monitoring

Standard anti-arrhythmic treatment

Treat withdrawal aggressively

Look for underlying cardiomyopathy especially if patient also has cirrhosis (the two conditions often co-exist)

Wernicke-Korsakoff syndrome


Wernicke’s: encephalopathy, ataxia, ophthalmoplegia

If untreated, causes permanent impairment of short-term memory (Korsakoff’s)

Difficult to diagnose in patients who are intoxicated or withdrawing

Repeated subclinical episodes may contribute to dementia

R/O other causes of encephalopathy or new-onset memory loss

Thiamine 100 mg IM od for 3 days

If you strongly suspect Wernicke’s (e.g., ophthalmoplegia): thiamine 100 mg IV daily

Do not give IV dextrose solutions until IM thiamine administered (glucose metabolism uses thiamine)


Table 2: Management of alcohol withdrawal in patients with other acute medical conditions

(Download a PDF of Table 2)


Clinical features


Hepatic encephalopathy

Cirrhotic patients in withdrawal at risk for encephalopathy if they receive benzodiazepines or have fluid and electrolyte disturbances


Low protein diet

Use diuretics judiciously

Avoid benzodiazepines; if severe withdrawal, use lorazepam 0.5 to 1 mg

Candidate for liver transplant if attends treatment, abstinent 6 months to 2 years


Very common in alcohol dependence

High suicide rate

Refer to psychiatric or addiction specialist if suicidal during withdrawal, or remains depressed after withdrawal resolved



Intensifies withdrawal, increases risk of delirium tremens

Associated with post-surgical arrhythmias, wound infections, prolonged hospital stay

Early and consistent diazepam loading, before surgery if possible

Elective surgery: Arrange outpatient alcohol withdrawal management. Refer to an addiction treatment program.


Contents of Dealing with Alcohol Problems


FAQ: Screening for alcohol problems

FAQ: Assessment of alcohol problems

FAQ: Treatment and management of alcohol problems

FAQ: Alcohol problems in women

FAQ: Alcohol use in pregnancy

FAQ: Older adults and alcohol

FAQ: Alcohol and major depression

Tools and resources

Patient information


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