What is the initial dose of gabapentin (Neurontin) for nerve pain?

Starting Dose of Gabapentin for Nerve Pain

Start gabapentin at 300 mg once daily at bedtime on Day 1, then increase to 300 mg twice daily on Day 2, and 300 mg three times daily (900 mg/day total) on Day 3. 1

Initial Titration Protocol

The FDA-approved dosing schedule provides the most straightforward approach for nerve pain:

• Day 1: 300 mg at bedtime
• Day 2: 300 mg twice daily (600 mg/day)
• Day 3: 300 mg three times daily (900 mg/day) 1

This rapid 3-day titration is supported by both the FDA label and major guidelines. 2, 3, 1

Target Therapeutic Dose

After reaching 900 mg/day on Day 3, continue titrating upward:

• Increase by 300 mg every 1-7 days until reaching the effective dose range 2
• Target dose: 1800 mg/day (600 mg three times daily), which represents the minimum effective dose for most patients 2, 1
• Maximum dose: 3600 mg/day if needed, though doses above 1800 mg/day may not provide additional benefit and increase side effects 2, 1

The evidence shows that 1800 mg/day is the threshold where efficacy is consistently demonstrated, with 32-38% of patients achieving at least 50% pain relief compared to 17-21% with placebo. 4

Special Population Adjustments

Elderly or medically frail patients require slower titration:

• Start at 100-300 mg at bedtime 2, 3
• Increase by 100-300 mg every 3-7 days (slower than standard patients) 2, 3
• This reduces dizziness and somnolence, which are more problematic in older adults 3

Renal impairment mandates dose reduction:

• For creatinine clearance 30-59 mL/min: start 200 mg twice daily 1
• For creatinine clearance 15-29 mL/min: start 200 mg once daily 1
• For creatinine clearance <15 mL/min: start 100 mg once daily 1

Timeline to Effectiveness

• Minimum trial duration: 3-8 weeks for titration plus 2 weeks at maximum tolerated dose 2
• Pain relief may take several weeks to manifest fully 3
• If 1800 mg/day is ineffective after an adequate trial, increase to 3600 mg/day before declaring treatment failure 2

Common Pitfalls to Avoid

Titrating too slowly: The FDA label demonstrates that rapid 3-day titration to 900 mg/day is safe and well-tolerated in most patients. 1 Unnecessarily slow titration delays therapeutic benefit.

Stopping at subtherapeutic doses: Many patients receive inadequate doses below 1800 mg/day. 5 The evidence clearly shows 1800-3600 mg/day is the effective range. 2, 5, 4

Inadequate trial duration: Gabapentin requires weeks to reach full effect. 2 Discontinuing before completing an adequate trial (minimum 5-10 weeks total) prevents proper assessment of efficacy.

Ignoring renal function: Gabapentin is renally cleared, and failure to adjust for renal impairment leads to drug accumulation and increased adverse effects. 3, 1

Managing Side Effects

The most common adverse effects are dizziness (19%), somnolence (14%), peripheral edema (7%), and gait disturbance (14%). 4 These are typically mild to moderate and resolve within 10 days of starting treatment. 5 If side effects are intolerable:

• Slow the titration schedule 2
• Consider switching to pregabalin, which has linear pharmacokinetics and may be better tolerated 2

Dosing Schedule Considerations

Gabapentin must be given three times daily at therapeutic doses due to nonlinear pharmacokinetics and saturable absorption. 2, 1 The maximum interval between doses should not exceed 12 hours. 1