What is the recommended dosage of bupropion (Zyban) for nicotine detoxification?

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Bupropion Dosage for Nicotine Detoxification

For smoking cessation, bupropion SR should be dosed at 150 mg once daily in the morning for the first 3 days, then increased to 150 mg twice daily (300 mg total daily dose) for 7-12 weeks, with treatment initiated 1-2 weeks before the target quit date. 1, 2

Standard Dosing Regimen

The titration schedule is critical for minimizing adverse effects while achieving therapeutic levels:

  • Days 1-3: 150 mg once daily in the morning 1, 2
  • Day 4 through Week 12: 150 mg twice daily (300 mg total daily dose) 1, 3, 2
  • Maximum dose: 300 mg per day for smoking cessation (do not exceed to minimize seizure risk) 1, 2

The second daily dose should be administered before 3 PM to minimize insomnia risk. 2

Treatment Timeline and Duration

Begin bupropion 1-2 weeks prior to the target quit date to allow therapeutic drug levels to be established before cessation attempts. 1, 2, 4 This pre-quit initiation is essential for optimal efficacy.

Standard treatment duration is 7-12 weeks, with efficacy formally assessed after this period. 1, 3, 2 Consider extending treatment to 6 months-1 year for patients who achieve successful cessation to prevent relapse. 3

Efficacy and Clinical Context

Bupropion SR increases 12-month abstinence rates by approximately 9-10 percentage points compared to placebo, with long-term abstinence rates of 30.3% versus 15.6% for placebo. 5, 4 While effective, varenicline remains the preferred first-line agent due to superior efficacy (nearly 3-fold increase in quit rates versus placebo), with bupropion serving as an effective alternative when varenicline is contraindicated or not tolerated. 6, 3

Combination Therapy

Bupropion can be safely combined with nicotine replacement therapy (NRT) for enhanced efficacy. 1, 3 The combination of bupropion SR plus nicotine patch achieved 35.5% abstinence at 12 months versus 30.3% for bupropion alone, though this difference was not statistically significant. 4

Common Side Effects and Management

The most frequent adverse effects include:

  • Insomnia (most common) - managed by ensuring second dose is before 3 PM 1, 2, 7
  • Dry mouth - generally transient and resolves without intervention 1, 7
  • Headache 7, 4
  • Nausea 7

These side effects are typically mild to moderate and often resolve quickly without therapeutic intervention. 7 If necessary, they can be managed by dose reduction. 7

Critical Contraindications and Precautions

Absolute contraindications include:

  • History or risk of seizure disorders (bupropion lowers seizure threshold) 1, 2
  • Eating disorders (bulimia or anorexia nervosa - increased seizure risk) 1, 2
  • Concurrent MAO inhibitor use or within 14 days of discontinuing MAOIs 1, 2
  • Concurrent tamoxifen use (drug interaction) 2
  • Severe hepatic cirrhosis 2
  • Uncontrolled hypertension 2

Seizure risk is approximately 0.1% (1 in 1,000) when patients are properly screened and the maximum dose of 300 mg/day is not exceeded. 5, 7

Dose Adjustments for Special Populations

  • Moderate to severe hepatic impairment: Maximum 150 mg daily (single dose) 2
  • Moderate to severe renal impairment (GFR <90 mL/min): Reduce total daily dose by 50% 2
  • Older adults: Consider starting at 37.5 mg daily and titrating by 37.5 mg every 3 days as tolerated 2

Monitoring and Follow-Up

  • First follow-up: Within 2-3 weeks of starting medication to assess tolerability and smoking status 3
  • Subsequent follow-up: At 12 weeks and at end of therapy 3
  • Monitor for: Neuropsychiatric symptoms (depression, agitation, behavioral changes), blood pressure, and seizure activity 2

Clinical Pearls

Bupropion may be particularly beneficial for patients with comorbid depression who want to quit smoking, as it addresses both conditions simultaneously through noradrenergic/dopaminergic pathways. 2

Bupropion significantly reduces weight gain during smoking cessation compared to placebo (1.7 kg versus 2.1 kg at 7 weeks). 4

If treatment fails after 7-12 weeks, consider switching to varenicline or intensifying behavioral therapy rather than continuing ineffective treatment. 3

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Bupropion Dosing and Administration

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Smoking Cessation with Oral Medications

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Bupropion SR for smoking cessation.

Expert opinion on pharmacotherapy, 2003

Guideline

Varenicline Prescription and Administration Guidelines for Smoking Cessation

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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