Can a patient with neuropathy take gabapentin (Neurontin) 800 mg in the morning, 800 mg at noon, and 1000 mg at bedtime?

Gabapentin Dosing: 800 mg AM, 800 mg Noon, 1000 mg Bedtime for Neuropathy

Yes, this gabapentin regimen (800 mg morning, 800 mg noon, 1000 mg bedtime = 2600 mg/day total) is appropriate and falls within the FDA-approved therapeutic range for neuropathic pain, provided the patient has normal renal function and has been properly titrated to this dose. 1

FDA-Approved Dosing Framework

• The FDA label explicitly states that gabapentin doses up to 3600 mg/day have been administered and well tolerated, with the recommended maintenance dose being 300-600 mg three times daily, and dosages up to 2400 mg/day having been well tolerated in long-term clinical studies 1
• The maximum time between doses should not exceed 12 hours, which this regimen satisfies 1
• Gabapentin can be administered using 600 mg or 800 mg tablets three times daily 1

Evidence-Based Therapeutic Range

• For postherpetic neuralgia and painful diabetic neuropathy, the FDA label demonstrates efficacy over a dose range of 1800-3600 mg/day, with comparable effects across this range 1
• Clinical trials show that 1800-3600 mg/day provides moderate-quality evidence for efficacy, with 32-38% of patients achieving at least 50% pain reduction 2, 3
• The proposed regimen of 2600 mg/day falls comfortably within this evidence-based therapeutic window 4, 3

Critical Titration Requirements

This dose should only be used if the patient has been gradually titrated upward from a starting dose. The proper titration schedule is:

• Start at 300 mg on day 1, increase to 600 mg/day on day 2, then 900 mg/day on day 3 1, 4
• Continue gradual increases by 300 mg every 3-7 days as tolerated until reaching the target dose 2, 5
• Allow 3-8 weeks for titration plus 2 weeks at maximum tolerated dose to properly evaluate efficacy 2

Never start at high doses (such as 800 mg) without gradual titration, as this dramatically increases the risk of intolerable adverse effects 2

Mandatory Renal Function Assessment

Before prescribing this dose, you must calculate creatinine clearance using the Cockcroft-Gault equation, as gabapentin is renally excreted and dose adjustment is mandatory in renal impairment 2, 1

The FDA provides specific dose reductions based on creatinine clearance:

• CrCl ≥60 mL/min: 900-3600 mg/day (no adjustment needed for this regimen) 1
• CrCl 30-59 mL/min: Maximum 1400 mg/day (this regimen would be too high) 1
• CrCl 15-29 mL/min: Maximum 700 mg/day (this regimen would be too high) 1
• CrCl <15 mL/min: Maximum 300 mg/day (this regimen would be too high) 1

Do not assume normal renal function based on serum creatinine alone—always calculate creatinine clearance 2

Expected Adverse Effects

• Dizziness (19%), somnolence (14%), peripheral edema (7%), and gait disturbance (9%) are the most common adverse effects 2, 3
• These effects are typically mild to moderate, dose-dependent, and often transient, usually subsiding within approximately 10 days 2, 4
• Adverse event withdrawals occur in 11% of patients versus 8.2% with placebo 3

Discontinuation Protocol

If gabapentin needs to be reduced, discontinued, or substituted, this must be done gradually over a minimum of 1 week 1

• Never abruptly discontinue gabapentin—taper gradually to avoid withdrawal symptoms 2, 5
• A longer taper period may be needed at the prescriber's discretion 1

Clinical Efficacy Expectations

• Approximately 38% of patients with painful diabetic neuropathy achieve substantial benefit (at least 50% pain relief) with gabapentin 1200 mg/day or greater, compared to 21% with placebo 3
• For postherpetic neuralgia, 32% achieve substantial benefit versus 17% with placebo 3
• An adequate trial requires 2 months or more to reach optimal effect 2

Critical Pitfalls to Avoid

• Do not prescribe this dose without confirming proper titration from lower doses 2, 4
• Do not fail to assess renal function before initiating or continuing therapy—this is non-negotiable 2, 1
• Do not use once-daily or twice-daily dosing for standard gabapentin—three times daily administration is essential due to saturable absorption 5
• Do not assume lack of efficacy if adequate time for titration and therapeutic trial (2+ months) has not been allowed 2