Alcohol Withdrawal Seizures

Pathophysiology

• ROSEN's Emergency Medicine, p. 3295

Timing and Clinical Features

• Typically generalized tonic-clonic (not focal)
• Occur 12-48 hours after the last drink; occasionally up to 5 days
• Most patients have a single seizure or a brief cluster (usually 2-3 seizures in rapid succession)
• Status epilepticus is rare in pure alcohol withdrawal
• Focal seizures or focal postictal deficits should prompt investigation for a structural, metabolic, or infectious cause
• About 2% of people with alcohol use disorder experience withdrawal seizures; risk increases with older age, concurrent medical problems, polydrug use, and higher baseline alcohol intake
• Bradley & Daroff's Neurology, p. 1803-1804
• Harrison's Principles 22E, p. 3723

Risk Factors for Seizures

• Prior history of alcohol withdrawal seizures or DTs (strongest predictor)
• Longer duration and higher quantity of alcohol use
• Older age
• Concomitant benzodiazepine or barbiturate use
• Medical comorbidities (liver disease, electrolyte abnormalities, infections)
• Hypoglycemia
• Hypomagnesemia (lowers seizure threshold independently)

Assessment: CIWA-Ar Scale

• ROSEN's Emergency Medicine, p. 3760

Differential Diagnosis

• Hypoglycemia (must give thiamine BEFORE glucose)
• Hyponatremia or other electrolyte disturbance
• Meningitis/encephalitis
• Subdural hematoma (trauma is common in this population)
• Hepatic encephalopathy
• Drug intoxication or co-withdrawal (benzodiazepines, barbiturates)
• Pre-existing epilepsy

• The Washington Manual, p. 1895
• Maudsley Prescribing Guidelines, p. 4593

Treatment

Immediate Seizure Management

• Benzodiazepines or phenobarbital are first-line - phenytoin is NOT effective for alcohol withdrawal seizures and should not be used
• IV diazepam 5-10 mg every 5-10 minutes or IV lorazepam 2-4 mg every 15-20 minutes, titrate to symptom control
• For status epilepticus in this context, escalate as per standard SE protocol with high-dose benzodiazepines

Prophylaxis and Withdrawal Management

• Long-acting benzodiazepines (chlordiazepoxide, diazepam) are the mainstay - they self-taper due to long half-life
  • Chlordiazepoxide 25-50 mg PO q6-8h (max 300 mg/day) with taper over 5 days
  • Diazepam 10 mg PO/IV q4-6h on day 1, taper to zero by day 5
• Liver disease: use short-acting benzodiazepines without active metabolites (lorazepam or oxazepam), as they are renally cleared
  • Oxazepam 15-30 mg PO q6-8h PRN
  • Lorazepam 1-4 mg IV (half-life increases less steeply with cirrhosis vs. diazepam)
• There is no proven benefit of prophylactic anticonvulsants in high-risk patients beyond adequate benzodiazepine loading
• Carbamazepine is used in some units for patients with breakthrough seizures despite benzodiazepines, or with untreated epilepsy
• Antipsychotics (haloperidol) may be used as adjuncts for agitation/behavioral control but never as monotherapy - they do not address underlying pathophysiology and lower seizure threshold

DTs (if present)

• ICU-level care required; mortality ~5% with treatment (was >30% historically)
• High-dose benzodiazepines (chlordiazepoxide up to 800 mg/day has been reported)
• Propofol or dexmedetomidine for refractory cases
• Antipsychotics are not recommended

Supportive Care

• IV thiamine 100-500 mg IM/IV (give before any glucose to prevent precipitating Wernicke encephalopathy)
• Oral thiamine 100 mg/day for at least 1 week
• Multivitamins with folate
• Electrolyte repletion: hypomagnesemia, hypokalemia, hypophosphatemia, and hypoglycemia are all common
• IV fluids only if clinically needed (most patients are euvolemic or mildly hypervolemic)
• Harrison's Principles 22E, p. 3723
• The Washington Manual, p. 1895-1901
• Maudsley Prescribing Guidelines, p. 4595-4601
• Bradley & Daroff's Neurology, p. 1804

Prognosis and Outpatient vs. Inpatient

1. Have mild withdrawal signs despite low blood alcohol levels
2. Have no prior history of DTs or withdrawal seizures
3. Are in good physical condition
4. Have reliable access to daily follow-up for 4-5 days

• Seizures peak at 12-48 hours; usually brief, self-limiting, generalized tonic-clonic
• Benzodiazepines are first-line for treatment AND prophylaxis; phenytoin is not effective
• Phenobarbital is an alternative to benzodiazepines
• Always give thiamine before glucose; check and correct electrolytes
• Focal seizures or status epilepticus should trigger workup for other causes
• DTs is a separate, later, life-threatening complication - not the same as seizures