What is the recommended dose of cyanocobalamin (Vitamin B12) for a patient with acute alcohol withdrawal?

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Cyanocobalamin Dosing for Acute Alcohol Withdrawal

No Specific Cyanocobalamin Dosing Recommendation Exists for Acute Alcohol Withdrawal

Cyanocobalamin (Vitamin B12) is not routinely indicated or dosed specifically for acute alcohol withdrawal management. The available guidelines do not provide dosing recommendations for cyanocobalamin in this clinical context 1.

What You Should Actually Be Giving: Thiamine

The critical vitamin supplementation in acute alcohol withdrawal is thiamine (Vitamin B1), not cyanocobalamin (Vitamin B12). This distinction is essential to prevent life-threatening complications 2, 3.

Thiamine Dosing for Acute Alcohol Withdrawal

  • Administer thiamine 100-300 mg IV daily for 3-5 days immediately upon presentation 3
  • For suspected Wernicke's encephalopathy, escalate to 500 mg IV three times daily 3
  • Always give thiamine BEFORE any glucose-containing IV fluids, as glucose can precipitate acute Wernicke's encephalopathy in thiamine-depleted patients 4, 3

Maintenance Therapy

  • Continue oral thiamine 50-100 mg/day for 2-3 months after resolution of acute withdrawal symptoms 4, 3
  • For prevention of Wernicke's encephalopathy: 100-300 mg/day for 4-12 weeks 4

When Cyanocobalamin Might Be Relevant

While not part of acute withdrawal management, cobalamin deficiency should be assessed in alcoholic patients who present with:

  • Anemia or isolated macrocytosis 1
  • Polyneuropathies 1
  • Neurodegenerative diseases or psychosis 1

Standard Cyanocobalamin Dosing (If Deficiency Identified)

  • Enteral nutrition: at least 2.5 mg daily in 1500 kcal 1
  • Parenteral nutrition: at least 5 mg daily 1

Critical Pitfall to Avoid

The most dangerous error is confusing B12 (cyanocobalamin) with B1 (thiamine). Thiamine deficiency affects 30-80% of alcohol-dependent patients and can cause fatal Wernicke's encephalopathy if not treated immediately 4. Cyanocobalamin does not prevent this complication and should not be substituted for thiamine 2, 3.

Complete Acute Alcohol Withdrawal Management

Beyond vitamin supplementation, acute alcohol withdrawal requires:

  • Benzodiazepines as first-line treatment (diazepam 10 mg initially, then 5-10 mg every 3-4 hours for severe withdrawal) 2
  • Fluid and electrolyte replacement with attention to magnesium levels 2
  • Continuous monitoring of vital signs for autonomic instability 2

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Management of Severe Alcohol Withdrawal

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Thiamine Supplementation Guidelines for Alcoholic Patients

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Thiamine Dosing for Alcoholic Patients with Fatty Liver Disease

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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