From the Guidelines
Gabapentin is primarily indicated for the treatment of partial seizures, postherpetic neuralgia, and various neuropathic pain conditions, with a recommended starting dose of 100-300 mg at bedtime or 100-300 mg three times daily, titrated to a maximum dose of 1800-3600 mg daily divided into three doses 1.
Indications for Gabapentin
- Partial seizures
- Postherpetic neuralgia
- Neuropathic pain conditions
- Off-label uses: fibromyalgia, restless leg syndrome, anxiety disorders, alcohol withdrawal, and hot flashes
Dosing Guidelines
- Starting dose: 100-300 mg at bedtime or 100-300 mg three times daily
- Titration: increase by 100-300 mg every 1-7 days as tolerated
- Maximum dose: 1800-3600 mg daily divided into three doses
- Renal impairment: dose adjustment required
- Elderly patients: lower doses may be required due to decreased renal function
Mechanism of Action
Gabapentin works by binding to voltage-gated calcium channels in the central nervous system, reducing the release of excitatory neurotransmitters.
Common Side Effects
- Dizziness
- Somnolence
- Peripheral edema
Important Considerations
- Dosing should be adjusted for patients with renal impairment
- The drug should be tapered gradually when discontinuing to avoid withdrawal symptoms
- Elderly patients may require lower doses due to decreased renal function
- Gabapentin has nonlinear pharmacokinetics, requiring careful titration 1
- The medication can produce dose-dependent dizziness and sedation, which can be reduced by starting with lower dosages and titrating cautiously 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). 2. 2 Dosage for Epilepsy with Partial Onset Seizures Patients 12 years of age and above The starting dose is 300 mg three times a day. 2. 3 Dosage Adjustment in Patients with Renal Impairment Dosage adjustment in patients 12 years of age and older with compromised renal function or undergoing hemodialysis is recommended, as follows
The indications for Gabapentin are:
- Postherpetic Neuralgia
- Epilepsy with Partial Onset Seizures The dosing guidelines for Gabapentin are:
- For Postherpetic Neuralgia: 300 mg on Day 1,600 mg/day on Day 2, and 900 mg/day on Day 3, titrated up as needed to a dose of 1800 mg/day
- For Epilepsy with Partial Onset Seizures:
- Patients 12 years of age and above: 300 mg three times a day, with a recommended maintenance dose of 300 mg to 600 mg three times a day
- Pediatric Patients Age 3 to 11 years: 10 mg/kg/day to 15 mg/kg/day, given in three divided doses, with a recommended maintenance dose reached by upward titration over a period of approximately 3 days
- Dosage adjustment is recommended for patients with renal impairment, with specific guidelines based on creatinine clearance values 2
From the Research
Indications for Gabapentin
- Gabapentin is commonly used to treat neuropathic pain (pain due to nerve damage) 3, 4, 5, 6
- Specific conditions where gabapentin is effective include:
Dosing Guidelines for Gabapentin
- Typical dosages of gabapentin used in studies are 1200 mg or more daily 3, 4, 5
- Doses of 1800 mg to 3600 mg daily may provide good levels of pain relief for some people with postherpetic neuralgia and peripheral diabetic neuropathy 3
- Gabapentin can be titrated rapidly, but it is essential to follow a healthcare professional's guidance to minimize adverse effects 6