What is the recommended dosage of bupropion (Wellbutrin) for obesity treatment?

Bupropion Dosage for Obesity Treatment

For obesity treatment, naltrexone-bupropion ER (Contrave) is recommended at a maintenance dose of bupropion SR 360 mg daily (combined with naltrexone 32 mg daily), following a gradual dose titration schedule to minimize side effects. 1, 2

Dosing Schedule and Titration

The recommended dosing schedule for naltrexone-bupropion (Contrave) is:

• Week 1: 1 tablet (naltrexone 8 mg/bupropion 90 mg) once daily in the morning
• Week 2: 1 tablet twice daily (morning and evening)
• Week 3: 2 tablets in the morning, 1 tablet in the evening
• Week 4 onwards: 2 tablets twice daily (maintenance dose)

This gradual titration is essential to minimize gastrointestinal side effects, particularly nausea, which affects up to 30% of patients 2, 3.

Efficacy for Weight Loss

Naltrexone-bupropion ER produces modest weight loss:

• Average weight loss of 4-6% greater than placebo at 56 weeks 3, 4
• Approximately 48-55% of patients achieve ≥5% weight loss at 56 weeks 3, 4
• Weight loss is comparable to other anti-obesity medications, with placebo-subtracted weight loss of approximately 4.0% 5

Special Dosing Considerations

1. Renal impairment:

   • Moderate to severe renal impairment: Reduce to 1 tablet twice daily
   • End-stage renal disease: Avoid use 2

2. Hepatic impairment:

   • Moderate to severe hepatic impairment: Limit to 1 tablet daily 2

3. Treatment response assessment:

   • If <5% weight loss after 12 weeks at maintenance dose, discontinue as patient is likely a poor responder 1, 2

Side Effects and Monitoring

Common side effects include:

• Gastrointestinal: Nausea (29.8%), constipation, vomiting (0.7-2%), dry mouth 2, 3
• Neurological: Headache (0.9-1.8%), dizziness (0.7-1.4%), insomnia 2

Important monitoring parameters:

• Blood pressure and heart rate, especially in first 12 weeks 1
• Mental health status (mood changes, suicidal thoughts) due to bupropion component 2
• Visual symptoms (refer to ophthalmologist if persistent) 2

Contraindications

Naltrexone-bupropion is contraindicated in:

• Seizure disorders or conditions that lower seizure threshold 1, 2
• Patients taking opioid medications 1, 2
• Concomitant use of MAOIs 2
• Uncontrolled hypertension 1
• Pregnancy 2
• History of anorexia or bulimia nervosa 2

Clinical Pearls

1. Bupropion alone (without naltrexone) has shown modest weight loss of approximately 2.8 kg at 6-12 months in clinical trials 1, but the combination with naltrexone provides enhanced efficacy.

2. Consider naltrexone-bupropion preferentially in patients with:

   • Comorbid depression (due to bupropion component) 1
   • Patients attempting smoking cessation 1

3. Discontinue medication before procedures requiring opioid pain management to avoid precipitating withdrawal 2

4. Patients with diabetes may experience modest improvements in glycemic control (0.6% reduction in HbA1c) 2

5. Approximately 25% of patients discontinue due to adverse effects 2