Maximum Daily Dose of Bupropion HCl ER (XL)
The maximum daily dose of bupropion hydrochloride extended-release (XL) is 450 mg per day, given as a single dose. 1
Dosing Algorithm
Standard Dosing for Major Depressive Disorder
- Initial dose: Start at 150 mg once daily in the morning
- Target dose: 300 mg once daily (can increase as early as day 4 if tolerated)
- Maximum dose: 450 mg once daily
The 450 mg maximum dose should only be considered for patients who show no clinical improvement after several weeks of treatment at 300 mg/day. 1
For Smoking Cessation
The maximum dose is 300 mg per day when used for smoking cessation, given as 150 mg twice daily. 2
Critical Safety Considerations
Seizure Risk Minimization
The gradual dose escalation is essential to minimize seizure risk—the most serious adverse effect of bupropion. 1 Key safety rules:
- Never crush, divide, or chew the XL tablets (increases seizure risk)
- Maintain at least 24 hours between doses
- Swallow tablets whole
Absolute Contraindications for Bupropion
Do not use in patients with:
- Seizure disorders or seizure risk factors (stroke, brain metastases)
- Current use of MAO inhibitors
- Concurrent tamoxifen use
- Closed-angle glaucoma 2
Dose Adjustments for Special Populations
Severe Hepatic Cirrhosis
- Maximum: 150 mg every other day (not daily)
- Use with extreme caution 1
Mild to Moderate Hepatic Impairment
- Reduce frequency and/or dose
- Use with caution 1
Renal Impairment
- Reduce frequency and/or dose
- Use with caution 1
Clinical Pearls
The FDA drug label explicitly states that doses above 300 mg/day have not been studied for seasonal affective disorder prevention. 1 For depression treatment, the full antidepressant effect may not be evident until 4 weeks or longer at the target dose, so wait several weeks at 300 mg/day before escalating to 450 mg/day. 1
Common manageable side effects include dry mouth, transient stomach discomfort, and headache. 3 Insomnia can be minimized by avoiding bedtime doses, though with XL formulation taken once in the morning, this is less of an issue. 1