What are the side effects of Wellbutrin (bupropion)?

Common and Serious Side Effects of Wellbutrin (Bupropion)

Bupropion commonly causes dry mouth, insomnia, headache, dizziness, nausea, constipation, and tremor, with seizures being a serious potential adverse effect requiring careful patient screening and dosage adherence. 1

Common Side Effects

• Neurological effects are among the most frequently reported side effects, including:

  • Insomnia (especially if taken close to bedtime) 1, 2
  • Headache 1
  • Dizziness 1
  • Tremor 1
  • Anxiety 3

• Gastrointestinal effects are also common:

  • Dry mouth (13% of patients) 1, 4, 5
  • Nausea 1
  • Constipation 1
  • Vomiting 1
  • Throat irritation 4

Serious Side Effects

• Seizures: Bupropion is associated with a seizure risk of approximately 1/1000 at recommended doses 1, 3

  • Risk factors include: prior history of seizures, structural brain lesions, alcohol abuse, and medications that lower seizure threshold 1
  • The maximum recommended daily dose is 450 mg for immediate-release and 400 mg for sustained-release formulations to minimize seizure risk 3, 2

• Cardiovascular effects:

  • Tachycardia and tachyarrhythmias can occur 1
  • Blood pressure should be monitored, particularly at treatment initiation 1
  • Patients with uncontrolled hypertension should avoid bupropion 1

• Psychiatric effects:

  • Increased risk of suicidal thoughts, especially in young adults 1, 2
  • May worsen pre-existing mental health problems 2
  • Can cause agitation, hostility, or aggression 2
  • Potential for manic episodes 2

Special Considerations and Contraindications

• Drug interactions:

  • Should not be used with monoamine oxidase inhibitors (MAOIs) due to risk of hypertensive crisis 1
  • Inhibits cytochrome P450-2D6 (CYP2D6), raising concern for drug interactions 6
  • Many medications can increase seizure risk when combined with bupropion 2

• Contraindicated in patients with:

  • History of seizures or conditions predisposing to seizures 1
  • Current or prior diagnosis of bulimia or anorexia nervosa 1
  • Recent discontinuation of alcohol, benzodiazepines, barbiturates, or antiepileptic drugs 1

Monitoring Recommendations

• Monitor for emergence of suicidal thoughts, especially during the first few weeks of treatment 1, 2
• Monitor blood pressure and heart rate periodically, especially during the first 12 weeks 1
• Watch for signs of seizure activity 1
• Pay close attention to any changes, especially sudden changes, in mood, behaviors, thoughts, or feelings 2

Unique Benefits

• Less likely to cause sexual dysfunction compared to many other antidepressants 6
• Does not typically cause weight gain 5
• May be beneficial for patients trying to quit smoking 1, 7

Administration Guidelines

• Swallow tablets whole; do not chew, cut, or crush (increases seizure risk) 2
• Take doses at least 24 hours apart 2
• May be taken with or without food 2
• Limit or avoid alcohol during treatment 2

Bupropion's unique mechanism of action (affecting dopamine and norepinephrine rather than serotonin) gives it a different side effect profile compared to SSRIs, making it a valuable alternative for patients who cannot tolerate other antidepressants 8, 6.