What formulation of bupropion (Zyban) is used for smoking cessation?

Bupropion Formulation for Smoking Cessation

The sustained release (SR) formulation of bupropion, marketed as Zyban, is the specific formulation used for smoking cessation. 1, 2

Dosage and Administration

• Starting dose: 150 mg once daily for the first 3 days
• Maintenance dose: 150 mg twice daily (300 mg total daily) for 7-12 weeks
• Timing: Begin treatment 1-2 weeks before the target quit date 1, 2
• Treatment may be extended up to 6 months or 1 year to promote continued cessation if needed 2

Mechanism of Action

Bupropion works by:

• Reducing nicotine withdrawal symptoms
• Modulating dopamine and norepinephrine reuptake
• Managing cravings during quit attempts
• Its efficacy in smoking cessation appears independent of its antidepressant effects 1, 2

Efficacy

• Bupropion SR significantly improves 12-month abstinence rates compared to placebo 1
• It reduces the severity of withdrawal symptoms 1
• Evidence shows it improves success at staying off cigarettes for at least 12 months by 9-10 percentage points 3

Contraindications

Bupropion SR is contraindicated in patients with:

• Seizure disorders or risk factors for seizures (stroke, brain metastases)
• Patients taking MAO inhibitors (risk of hypertensive reactions)
• Patients taking tamoxifen
• Closed-angle glaucoma
• History of eating disorders 1, 2, 4

Side Effects and Monitoring

• Common side effects: Insomnia, dry mouth, headache, nausea 5, 6
• Serious but rare side effects:
  • Seizures (risk approximately 1 in 1000) 1, 6
  • Allergic/hypersensitivity reactions (1 in 1000 to 1 in 10,000) 1, 6
  • Neuropsychiatric symptoms including depression, hostility, and suicidal behavior 1, 4

Important Clinical Considerations

• Monitor for development or worsening of neuropsychiatric issues, particularly in patients with a history of psychiatric disorders 1, 2
• Bupropion SR may help reduce weight gain associated with smoking cessation 2
• Combining bupropion with nicotine replacement therapy may enhance efficacy for some patients 2
• Patients should be instructed to take tablets whole, not crushed, divided, or chewed 4
• Bupropion should not be used in combination with other medications containing bupropion 4

Special Populations

• Evidence on effectiveness is limited to medium to heavy smokers (15+ cigarettes per day) receiving behavioral support 1
• Limited evidence exists for use in light smokers or those with a history of depression 2
• Consider dose reduction for patients with moderate to severe hepatic or renal impairment 2

Bupropion SR (Zyban) should be used in conjunction with motivational support or behavioral counseling to maximize smoking cessation success rates 3, 6.