What is the maximum dose of bupropion sustained‑release for weight loss in a 28‑year‑old male weighing 522 lb with a colostomy and hernia who is currently taking 150 mg daily?

Maximum Dose of Bupropion SR for Weight Loss

The maximum dose of bupropion sustained-release (SR) for weight loss is 450 mg per day, administered as 150 mg twice daily in the morning and early afternoon, with the second dose taken before 3 PM to minimize insomnia risk. 1

FDA-Approved Maximum Dosing

• The FDA label specifies that the maximum dose for bupropion SR is 400 mg per day, while bupropion XL can be dosed up to 450 mg per day. 1, 2
• For weight management specifically using the naltrexone-bupropion ER combination (Contrave), the maximum bupropion component is 360 mg per day (32 mg naltrexone/360 mg bupropion daily). 1
• Exceeding 450 mg per day markedly increases seizure risk above the baseline 0.1% rate, making this an absolute ceiling. 1, 2

Current Dosing and Titration for Your Patient

Since your patient is currently taking 150 mg daily and has lost 2.4 pounds in one week:

Recommended Titration Schedule

• Week 1 (current): 150 mg once daily in the morning 1
• Week 2: Increase to 150 mg twice daily (300 mg total) – first dose in the morning, second dose before 3 PM 1
• Assess response at 6-8 weeks before considering further dose increases 1
• If inadequate weight loss after 8 weeks at 300 mg/day: May increase to 150 mg three times daily (450 mg total) for bupropion XL formulation only, or remain at 400 mg/day maximum for SR formulation 1, 2

Critical Safety Considerations for This Patient

Seizure Risk Monitoring

• At the standard 300 mg/day dose, seizure risk is approximately 0.1% (1 in 1,000 patients). 1, 3, 4
• The patient's extreme obesity (522 pounds) does not independently contraindicate bupropion, but the presence of a hernia and colostomy requires careful assessment for any history of head trauma, brain lesions, or metabolic abnormalities that could lower seizure threshold. 1, 2
• Screen for: history of seizures, eating disorders (bulimia/anorexia), alcohol use requiring abrupt discontinuation, concurrent medications that lower seizure threshold, and uncontrolled hypertension. 1, 2

Blood Pressure Monitoring

• Measure baseline blood pressure before increasing the dose, as bupropion can elevate both blood pressure and heart rate. 1, 2
• Monitor blood pressure at least weekly for the first 12 weeks, especially when titrating doses. 1
• Uncontrolled hypertension is an absolute contraindication to dose escalation. 1, 2

Expected Weight Loss Outcomes

• In clinical trials, bupropion monotherapy at 300 mg/day produced mean weight loss of 4.9% at 8 weeks in overweight women, with 67% losing over 5% of baseline body weight. 5
• Responders who continued treatment for 24 weeks achieved 12.9% weight loss, with fat accounting for 73.5% of weight lost. 5
• For your 522-pound patient, a 5% weight loss target would be approximately 26 pounds at 8-12 weeks, which would represent clinically meaningful progress toward surgical candidacy. 5

Practical Dosing Algorithm

If weight loss ≥1 pound per week at current dose:

• Continue 150 mg daily for another week, then increase to 150 mg twice daily (300 mg total). 1

If weight loss plateaus at 300 mg/day after 8 weeks:

• Consider increasing to 400-450 mg/day (depending on formulation) OR
• Add behavioral interventions (reduced portion size, increased fiber intake) before dose escalation. 6

If inadequate response (<5% weight loss) at maximum dose after 12 weeks:

• Discontinue bupropion and consider alternative weight-loss medications such as liraglutide 3.0 mg subcutaneously daily (no seizure risk) or metformin up to 2500 mg/day. 6, 7

Timing of Second Daily Dose

• The second dose must be administered before 3 PM to prevent insomnia, which is the most common adverse effect (occurring in approximately 4% of patients on bupropion versus placebo). 1, 3
• Insomnia is also a nicotine withdrawal symptom, so if the patient smokes, this side effect may be more pronounced. 3

Common Adverse Effects to Monitor

• Most common: Insomnia (4%), dry mouth (20%), headache, nausea, and anxiety. 6, 3
• These effects are typically transient and resolve within 4-5 days without intervention, but can be managed by temporary dose reduction if necessary. 8, 3
• Discontinuation rates due to adverse events in clinical trials were only 6-12%, indicating good overall tolerability. 3

Contraindications That Must Be Ruled Out

Before increasing to maximum dose, confirm the patient does NOT have:

• Current or past seizure disorder 1, 2
• Eating disorder (bulimia or anorexia nervosa) 6, 1
• Current MAOI use or use within 14 days 1, 2
• Abrupt discontinuation of alcohol, benzodiazepines, or antiepileptic drugs 1
• Moderate to severe hepatic impairment (maximum 150 mg/day in this population) 1
• Moderate to severe renal impairment (reduce dose by 50% if GFR <90 mL/min) 1