From the Guidelines
Gabapentin therapy should be initiated at a low dose of 100-300 mg at bedtime or 100-300 mg three times daily and gradually increased to minimize side effects, with a maximum dosage of 3600 mg daily in divided doses, as recommended by recent guidelines 1. The recommended starting dose can be increased by 100-300 mg every 1-7 days as tolerated, with a duration of adequate trial being at least 3-8 weeks for titration plus 2 weeks at maximum dose 1. For elderly patients or those with renal impairment, lower starting doses and slower titration are advised, with dose adjustments required for those with renal insufficiency 1. When discontinuing gabapentin, it should be tapered gradually over at least one week to avoid withdrawal symptoms such as anxiety, insomnia, nausea, pain, and sweating. Key considerations in the management of gabapentin therapy include:
- Starting with a low dose and gradually increasing to minimize side effects
- Monitoring patient response and tolerability to guide dose titration
- Adjusting doses for elderly patients or those with renal impairment
- Tapering gradually when discontinuing gabapentin to avoid withdrawal symptoms
- Considering the use of food to reduce gastrointestinal side effects and adjusting evening doses to optimize sedation benefits. The most recent and highest quality study recommends a starting dose of 100-300 mg nightly, with increments of 50%-100% every few days, and a maximum dose of 3600 mg daily in divided doses 1.
From the FDA Drug Label
Dosage and Administration 2. 1 Dosage for Postherpetic Neuralgia In adults with postherpetic neuralgia, gabapentin may be initiated on Day 1 as a single 300 mg dose, on Day 2 as 600 mg/day (300 mg two times a day), and on Day 3 as 900 mg/day (300 mg three times a day). The starting dose is 300 mg three times a day. The recommended maintenance dose of gabapentin tablets is 300 mg to 600 mg three times a day. The starting dose range is 10 mg/kg/day to 15 mg/kg/day, given in three divided doses, and the recommended maintenance dose reached by upward titration over a period of approximately 3 days.
To start someone on gabapentin, the dose and taper schedule is as follows:
- For adults with postherpetic neuralgia:
- Day 1: 300 mg single dose
- Day 2: 600 mg/day (300 mg two times a day)
- Day 3: 900 mg/day (300 mg three times a day)
- For patients 12 years of age and above with epilepsy:
- Starting dose: 300 mg three times a day
- Maintenance dose: 300 mg to 600 mg three times a day
- For pediatric patients age 3 to 11 years:
- Starting dose range: 10 mg/kg/day to 15 mg/kg/day, given in three divided doses
- Maintenance dose reached by upward titration over a period of approximately 3 days 2
From the Research
Gabapentin Dosing and Tapering Schedule
To initiate gabapentin (Neurontin) therapy, the following dosing and tapering schedule is recommended:
- Start with a low dose: 300 mg on day 1,600 mg on day 2, and 900 mg on day 3 3
- Titrate the dose as needed: up to 1800 mg/d for greater efficacy, and up to 3600 mg/d for some patients 3
- Individualize the dose: according to patient response and tolerability 3
Special Considerations
For patients with end-stage renal disease maintained on hemodialysis:
- Initial loading dose: 300-400 mg 4
- Maintenance dose: 200-300 mg after every 4 hours of hemodialysis 4 For patients with decreased renal function:
- Dosage adjustment: may be necessary for patients with creatinine clearance (CLcr) < 60 mL/min 5
Tapering Schedule
When discontinuing gabapentin, a tapering schedule is recommended to minimize the risk of withdrawal symptoms:
- Gradually reduce the dose: over a period of at least 1 week 6
- Monitor for withdrawal symptoms: such as anxiety, insomnia, and nausea 6
Important Notes
- Gabapentin is not bound to plasma proteins and is cleared solely by renal excretion 4
- The elimination half-life of gabapentin is approximately 132 hours in patients with normal renal function, and approximately 4 hours during hemodialysis 4
- Gabapentin has been shown to be effective in the treatment of neuropathic pain, including postherpetic neuralgia and painful diabetic neuropathy 6, 3