What are the dosage and potential side effects of Wellbutrin (bupropion)?

Wellbutrin (Bupropion): Dosage and Side Effects

Wellbutrin (bupropion) is typically dosed at 150-300 mg daily for the sustained-release (SR) formulation and 150-450 mg daily for the extended-release (XL) formulation, with common side effects including insomnia, dry mouth, headache, and nausea, while seizures represent the most serious potential adverse effect. 1, 2, 3

Dosage Information

Sustained-Release (SR) Formulation

• Initial dose: 100-150 mg once daily 1
• Maintenance dose: 100-150 mg twice daily (total 200-300 mg/day) 1, 2
• Dose is usually adjusted every 7-14 days to minimize side effects 2

Extended-Release (XL) Formulation

• Initial dose: 150 mg once daily in the morning 1, 2
• Maintenance dose: 150-300 mg once daily 1, 2
• Maximum dose: 450 mg per day 1, 3

Special Population Considerations

• For moderate to severe hepatic impairment: Maximum dose should not exceed 150 mg daily 3
• For moderate to severe renal impairment: Total daily dose should be reduced by half 2
• Elderly patients: Consider starting at lower doses (approximately 50% of standard dose) 2

Common Side Effects

Neurological/Psychological

• Insomnia (avoid taking doses close to bedtime) 3
• Headache 3
• Dizziness 3
• Anxiety 3
• Agitation 4

Gastrointestinal

• Dry mouth 3, 5
• Nausea 3
• Constipation 3

Other Common Side Effects

• Joint aches 3
• Stuffy nose 3

Serious Side Effects and Precautions

Seizure Risk

• Seizures are the most serious potential adverse effect, occurring in approximately 0.1% of patients at therapeutic doses 6, 4
• Risk factors for seizures include:
  • Doses exceeding 450 mg per day 1, 7
  • History of seizure disorders 1, 8
  • Brain injuries or tumors 1
  • Eating disorders 8
  • Abrupt discontinuation of alcohol or sedatives 8

Cardiovascular Effects

• May cause elevated heart rate and blood pressure 1
• Use with caution in patients with cardiovascular disease 8

Neuropsychiatric Effects

• May increase risk of suicidal thoughts or behaviors, especially in young adults under 24 years 8
• Monitor for worsening depression or unusual changes in behavior 1

Contraindications

• Seizure disorders 1, 8
• Current or prior diagnosis of bulimia or anorexia nervosa 8
• Undergoing abrupt discontinuation of alcohol or sedatives 8
• Use of monoamine oxidase inhibitors (MAOIs) within 14 days 1, 8
• Pregnancy and breastfeeding (use with caution) 1
• Severe hepatic impairment 3

Important Administration Guidelines

• Swallow tablets whole; do not chew, crush, or divide tablets 3
• Take at least 24 hours apart for once-daily dosing 3
• May be taken with or without food 3
• If a dose is missed, wait until the next scheduled dose (do not double-dose) 3
• Limit or avoid alcohol consumption during treatment 3

Overdose Considerations

• Overdoses of bupropion can cause seizures in approximately one-third of cases 3
• Other serious overdose effects include hallucinations, loss of consciousness, cardiac arrhythmias, and mental status changes 3
• No specific antidote exists; treatment is supportive 3

Bupropion offers the advantage of minimal sexual side effects compared to many other antidepressants, making it a preferred option for patients concerned about this issue 8, 4. However, the risk of seizures, especially at higher doses, necessitates careful patient selection and dosing 6, 9.