What are the side effects of bupropion (Wellbutrin)?

Side Effects of Bupropion (Wellbutrin)

Bupropion commonly causes dry mouth, insomnia, headache, and dizziness, with a small but serious risk of seizures (1/1000) especially in those with predisposing factors. The most common side effects of bupropion include dry mouth, insomnia, headache, dizziness, nausea, constipation, and tremor, with seizures being the most serious potential adverse effect requiring careful patient screening and dosage adherence. 1, 2

Common Side Effects

• Neurological effects: Insomnia, headache, dizziness, and tremor are among the most frequently reported side effects 1
• Gastrointestinal effects: Dry mouth, nausea, constipation, and vomiting 1
• Psychological effects: Anxiety, agitation, and irritability 2, 3

These common side effects are often dose-related and may be transient, resolving without therapeutic intervention. If necessary, they can be managed by reducing the bupropion dose 4.

Serious Side Effects

Seizure Risk

• Bupropion has been associated with a small increased incidence of seizures (rate of 1/1000) 1
• Risk factors for seizures include:
  • Prior history of seizures
  • Structural brain lesions from previous stroke, tumor, trauma
  • Alcohol abuse
  • Concomitant medications that lower seizure threshold 1, 2
• To minimize seizure risk:
  • Screen patients for predisposing risk factors
  • Adhere to manufacturer's dosage recommendations (maximum daily dose of 300mg) 4
  • Avoid in patients with a history of seizure disorders 1

Psychiatric Effects

• Bupropion carries a black box warning related to potential increase in suicidal thoughts in young adults within the first few months of treatment initiation 1, 2
• Patients should be monitored closely for:
  • New or worsening depression
  • Unusual changes in behavior or mood
  • Suicidal thoughts or actions 2
• Manic episodes may occur, particularly in patients with bipolar disorder 2

Special Considerations

Drug Interactions

• Bupropion should not be used with:
  • Monoamine oxidase inhibitors (MAOIs) due to risk of hypertensive crisis 1
  • Opioids, as bupropion may reduce their efficacy or precipitate withdrawal 1
• Bupropion inhibits CYP2D6, potentially increasing levels of drugs metabolized by this enzyme 5

Cardiovascular Effects

• May cause increased blood pressure, particularly when combined with nicotine replacement therapy 2
• Should be used with caution in patients with cardiovascular disease 1

Discontinuation

• Never stop bupropion suddenly without consulting a healthcare provider 2
• Abrupt discontinuation can cause withdrawal symptoms 2

Patient Selection Considerations

• Bupropion may be a good choice for patients with:

  • Concomitant depression who are trying to quit smoking 1
  • Concerns about sexual dysfunction (bupropion has lower rates compared to other antidepressants) 3, 6
  • Concerns about weight gain (less common with bupropion) 6

• Bupropion should be avoided in patients with:

  • Uncontrolled hypertension 1
  • History of seizures or conditions predisposing to seizures 1
  • Eating disorders such as anorexia or bulimia nervosa 1
  • Recent discontinuation of alcohol, benzodiazepines, barbiturates, or antiepileptic drugs 1

Monitoring Recommendations

• Monitor for emergence of suicidal thoughts, especially in young adults 2
• Monitor blood pressure, particularly at treatment initiation 2
• Watch for signs of seizure activity 1
• Assess for mood changes, including potential manic symptoms 2

By understanding these side effects and taking appropriate precautions, healthcare providers can help patients safely benefit from bupropion therapy while minimizing adverse effects.