Gabapentin Dosing for Alcohol Use Disorder Treatment
For alcohol use disorder treatment, gabapentin should be dosed at 900-1800 mg/day divided into three doses, with 1800 mg/day showing the best efficacy for maintaining abstinence. 1
Evidence-Based Dosing Regimen
Gabapentin has emerged as an effective off-label medication for alcohol use disorder (AUD) treatment. The dosing regimen should follow this algorithm:
- Starting dose: Begin with 300 mg three times daily (900 mg/day)
- Target dose: Increase to 600 mg three times daily (1800 mg/day) as tolerated
- Duration: Maintain treatment for at least 12 weeks
This dosing recommendation is based on a high-quality randomized clinical trial that demonstrated dose-dependent efficacy, with the 1800 mg/day dose showing superior outcomes compared to 900 mg/day 1. The higher dose (1800 mg/day) resulted in a 17% abstinence rate compared to 11.1% at 900 mg/day and only 4.1% with placebo.
Dose Adjustments for Special Populations
Dose adjustments are necessary for patients with renal impairment:
| Creatinine Clearance (mL/min) | Total Daily Dose Range (mg/day) | Dose Regimen |
|---|---|---|
| ≥60 | 900-1800 | 300-600 mg TID |
| 30-59 | 400-1400 | 200-700 mg BID |
| 15-29 | 200-700 | 200-700 mg QD |
| ≤15 | 100-300 | 100-300 mg QD |
Monitoring and Safety Considerations
- Monitor for neurological adverse effects: Gabapentin is associated with increased risk of falls, fractures, and altered mental status, particularly at doses ≥600 mg/day 3
- Dose-response relationship: Higher risk of adverse events is observed with doses ≥2400 mg/day, so the recommended maximum of 1800 mg/day for AUD stays within a safer range 3
- Patients with liver disease: Unlike naltrexone, disulfiram, and nalmefen (which are contraindicated in hepatic insufficiency), gabapentin does not undergo hepatic metabolism and may be safer for patients with AUD who have concurrent liver disease 4
Efficacy Outcomes
The 1800 mg/day dose of gabapentin has demonstrated:
- Number needed to treat (NNT) of 8 for complete abstinence
- NNT of 5 for preventing heavy drinking
- Significant improvements in mood, sleep, and alcohol craving 1
Clinical Context
While the American Association for the Study of Liver Diseases (AASLD) mentions gabapentin as a potential medication for AUD 4, it is not FDA-approved for this indication. However, its safety profile in patients with liver disease makes it a valuable option, particularly when FDA-approved medications like naltrexone are contraindicated due to hepatotoxicity concerns.
A Thai study using lower doses (minimum 300 mg/day) also showed efficacy in reducing heavy drinking days, suggesting that even lower doses may provide some benefit when higher doses cannot be tolerated 5.
Important Caveats
- Gabapentin should be used in conjunction with psychosocial interventions for optimal outcomes
- When combined with alcohol, gabapentin may enhance alcohol-induced tachycardia in a dose-dependent manner 6
- Patients should be monitored for sedation, especially when initiating therapy or increasing doses
By following this evidence-based dosing approach, clinicians can optimize the benefits of gabapentin for AUD treatment while minimizing potential risks.