Naltrexone Dosing for Binge Eating Disorder
Naltrexone is not FDA-approved for binge eating disorder, and the most recent APA guidelines (2023) do not recommend it as a first-line treatment—instead, prioritize cognitive-behavioral therapy or interpersonal therapy, with lisdexamfetamine or antidepressants as medication options if needed 1.
Critical Context: Off-Label Use
The FDA label for naltrexone only covers alcohol dependence (50 mg daily) and opioid dependence (25-50 mg daily), with no approved indication for binge eating disorder 2. When naltrexone has been studied for binge eating, it has typically been used in combination with bupropion (naltrexone/bupropion or NB), not as monotherapy.
Dosing Regimens Used in Research
When naltrexone has been investigated for binge eating disorder, the following dosing patterns emerge from clinical trials:
Naltrexone/Bupropion Combination (Most Common)
- Standard dose: Naltrexone 32 mg/bupropion 360 mg daily (sustained release formulation) 3
- Alternative dose: Naltrexone 50 mg/bupropion 300 mg XL daily 4
- These combination products are titrated over several weeks to minimize side effects, particularly nausea
Naltrexone Monotherapy (Historical Data)
- Low-dose regimen: 50-100 mg daily showed no significant benefit in older studies 5
- High-dose regimen: 200-300 mg daily showed reductions in binge eating and purging in bulimia nervosa, but this dose range carries increased hepatotoxicity risk 5
- Moderate dose: 100-150 mg daily showed modest effects in one 8-week trial 6
Evidence Quality and Efficacy
The evidence for naltrexone in binge eating disorder is weak and inconsistent:
- Recent meta-analyses (2025) found no significant reduction in binge eating frequency with naltrexone/bupropion compared to placebo 7, 8
- Weight loss was achieved (approximately 3.5 kg reduction), but this doesn't address the core eating disorder psychopathology 7
- A 2021 pilot RCT showed no significant difference between naltrexone/bupropion and placebo for binge eating outcomes 4
- One meta-analysis of opioid antagonists broadly (not specific to BED) suggested benefit at higher naltrexone doses, with dosage serving as a moderator 9
Clinical Algorithm: When to Consider Naltrexone
Step 1: Start with guideline-recommended treatments
- Eating disorder-focused CBT or interpersonal therapy (individual or group) 1
Step 2: If psychotherapy fails or patient prefers medication
- Consider lisdexamfetamine (FDA-approved for BED) or antidepressants first 1
Step 3: If considering naltrexone/bupropion as off-label option
- Use only in patients with comorbid obesity where weight loss is a priority
- Screen for contraindications: seizure disorders, eating disorders with purging, uncontrolled hypertension, opioid use
- Dose: Naltrexone 32 mg/bupropion 360 mg SR daily (or naltrexone 50 mg/bupropion 300 mg XL)
- Titrate slowly over 4 weeks to target dose
- Monitor liver function tests at baseline (naltrexone carries hepatotoxicity risk, especially above 50 mg daily) 2
Critical Caveats
Hepatotoxicity warning: The FDA label explicitly warns that doses above 50 mg daily carry higher risk of liver injury 2. Historical studies using 200-300 mg daily for eating disorders predate this safety concern.
Placebo effect: Obese patients with binge eating show strong placebo responses in trials, making it difficult to demonstrate medication superiority 6.
Mechanism mismatch: While naltrexone targets opioid-mediated reward pathways, current evidence suggests this may reduce caloric intake and weight but not the frequency or psychological drivers of binge eating episodes 10, 7.
Combination therapy rationale: Bupropion alone and naltrexone alone have limited efficacy; the combination theoretically enhances dopaminergic and reduces opioidergic signaling in reward circuits, but clinical trials have not consistently validated this mechanism for binge eating 4, 7, 8.