What are the side effects of Wellbutrin (bupropion)?

Common Side Effects of Wellbutrin (Bupropion)

Wellbutrin (bupropion) commonly causes insomnia, headache, dry mouth, nausea, anxiety, constipation, dizziness, and joint aches, with seizures being the most serious potential adverse effect that occurs in approximately 0.1% of patients at recommended doses. 1, 2

Most Common Side Effects

• Insomnia and dry mouth occur significantly more frequently with bupropion than with placebo 3
• Other common side effects include:
  • Headache 1, 3
  • Nausea 2, 1
  • Anxiety 1, 3
  • Constipation 2, 1
  • Dizziness 2, 1
  • Joint aches 1
  • Stuffy nose 1

Serious Side Effects

Seizure Risk

• The risk of seizures is approximately 0.1% at recommended doses 3, 4
• Seizure risk increases with higher doses of bupropion 1
• The National Comprehensive Cancer Network recommends starting with low doses and increasing gradually to minimize seizure risk 4
• Bupropion should be avoided in patients with:
  • History of seizures 4, 1
  • Brain metastases 4
  • Other conditions that elevate seizure risk 4, 1

Cardiovascular Effects

• Bupropion may cause increased blood pressure, particularly when used with nicotine replacement therapy 1
• Weak evidence suggests venlafaxine may have a higher risk for cardiovascular events than bupropion 2

Neuropsychiatric Effects

• Bupropion can cause:
  • Suicidal thoughts or behaviors, especially in young adults under 24 years 5, 1
  • Manic episodes 1
  • Agitation 1, 6
  • Depression 1
  • Hostility 1

Hypersensitivity Reactions

• Severe hypersensitivity reactions occur in approximately 0.1% of patients 3
• Delayed allergic reactions can appear 2 or more weeks after starting bupropion 7
• Risk may be highest in males aged 17-40 years and those with a history of allergic reactions 7

Sexual Side Effects

• Bupropion has a significantly lower rate of sexual adverse events compared to many other antidepressants, particularly SSRIs like fluoxetine or sertraline 2, 8
• This makes it a potential option for patients concerned about sexual dysfunction 8

Precautions and Contraindications

• Do not use bupropion with monoamine oxidase inhibitors (MAOIs) or within 14 days of stopping MAOIs 5, 1
• Limit or avoid alcohol during treatment with bupropion 1
• Do not drive or use heavy machinery until you know how bupropion affects you 1
• Bupropion can cause false positives for amphetamines in urine drug screening tests 1

Special Populations

• For patients with moderate to severe hepatic impairment, the total daily dose should not exceed 150 mg 5
• For moderate to severe renal impairment, the total daily dose should be reduced by half 5
• Two case reports noted seizures in breastfed infants whose mothers were taking bupropion 4

Clinical Pearls

• Most side effects are transient and often resolve without intervention 3
• If insomnia occurs, taking the second dose before 3 p.m. may help 5
• The maximum recommended daily dose is 450 mg to minimize seizure risk 5
• Bupropion should be taken at least 24 hours apart between doses 1

Understanding these side effects can help patients and providers make informed decisions about using bupropion for depression or smoking cessation, with appropriate monitoring for adverse reactions.