What to Know About Gabapentin

The Generic Version of Neurontin

Gabapentin is a generic prescription drug with several uses

Brian Pieters / Getty Images

In This Article

Gabapentin is an oral prescription medication used for treatment of seizures and some types of neuropathic pain. Gabapentin is a generic formulation, and there are several brand versions of the drug. There are specific recommended doses of gabapentin for each condition, and your doctor may also adjust your dose to achieve a therapeutic effect with minimal side effects. 

Uses

Gabapentin is used for the treatment of conditions that involve seizures or pain.

Approval

  • Postherpetic neuralgia: Approved only for adults 
  • Epilepsy: Approved for adults and children age 3 and older

Postherpetic neuralgia is a pain condition that can develop after a bout of shingles.

Gabapentin is used as an adjunctive anticonvulsant for prevention of partial onset seizures. Gabapentin is not considered effective for seizure prevention when used on its own. As an adjunctive treatment, it should be used along with another anticonvulsant.

Partial onset seizures (also called focal seizures) are seizures that are known to begin on one area of the brain. These types of seizures may or may not generalize (spread to involve the rest of the brain).

Gabapentin is not effective for seizures that begin throughout the whole brain, and it can be used for partial onset seizures that generalize or that do not generalize.

According to the manufacturer, the mechanism of action of gabapentin is unknown.

Off-Label Uses 

Gabapentin is often prescribed off-label. There are a number of off-label uses of gabapentin, including fibromyalgia, nausea, migraine prevention, and alcohol withdrawal, and other types of neuropathic pain besides postherpetic neuralgia.

While off-label use can be safe, there are some concerns about the safety and potential side effects of off-label use of gabapentin.

Before Taking

This medication is not established as safe for for people who are pregnant or breastfeeding. There is a high risk of side effects for people who are elderly.

Precautions and Contraindications 

Gabapentin can cause severe dizziness or sleepiness. If you drive or operate equipment that could be dangerous, you need to be careful when taking gabapentin. 

There have also been concerns about harmful misuse of gabapentin, so it is important that you only use this medication as prescribed.

Other Drug Names 

Gabapentin is a generic formulation. Brand name versions of gabapentin include Neurontin and Horizant.

Dosage

The generic form of gabapentin comes in 100 milligrams (mg), 300 mg, and 400 mg capsules, 600 mg, and 800 mg tablets, and a 250 mg per 5 milliliters (mL) oral solution. The 600 mg and 800 mg tablets are scored and can be divided in half. 

Postherpetic Neuralgia 

When it’s used for treating postherpetic neuralgia, gabapentin is started at a low dose and increased over the course of a few days to a maximum recommended dose of 1800 mg/day.

According to the manufacturer, the recommend gabapentin schedule for the treatment of postherpetic neuralgia is as follows: 

  • Day 1: 300 mg once per day 
  • Day 2: 300 mg twice per day
  • Day 3: 300 mg three times a day

Epilepsy 

When it’s used for seizure prevention in epilepsy, the gabapentin dose is based on age and weight. It should be started at a low dose and increased to the target dose over the course of about three days. 

Manufacturer recommended doses:

Adults and children age 12 and older: The starting dose is 300 mg three times daily. Gabapentin can be increased up to 600 mg three times daily, if needed.

Children between ages 3 to 11: Gabapentin is started at 10 to 15 mg per kilogram (kg) of body weight per day, divided into three doses:

  • The target dose for children who are 3 or 4 years old is 40 mg per kg of body weight per day, divided into three doses.
  • The target dose for children who are between 5 and 11 years old is 25 to 35 mg per kg of body weight per day, divided into three doses. 

Modifications

If you have kidney insufficiency or if you get hemodialysis, you would need to have a lower than recommended dose of gabapentin. Your adjusted dose would be based on your creatinine clearance.

If your creatinine clearance is less than 15 mL/min, your gabapentin dose should be reduced in proportion to your reduced percentage of creatinine clearance as compared to normal. 

How to Take and Store 

You should swallow your gabapentin with water and without crushing the tablets or capsules. You can take your gabapentin with or without food.

Gabapentin tablets and capsules should be stored at a temperature of 25 C (77 F). The oral solution should be stored in a refrigerator at a temperature between 2 C to 8 C (36 F to 46 F).

Side Effects

The side effects of gabapentin differ depending on the condition that it is being taken for and the age of the person taking it.

There are several reasons for the range of side effects. Varying doses with each condition and age differences can result in correspondingly varied concentration of the drug in the body. Additionally, the underlying medical condition may affect the way the medication interacts with the body. 

Common 

Sometimes the side effects are dose related and might improve with a lower gabapentin dose, but you may have persistent side effects even with lower doses.

If your side effects persist with the minimum dose that’s effective, you might need to stop taking gabapentin. You and your doctor will have to discuss this option together. 

Common side effects of gabapentin:

  • When used for postherpetic neuralgia: Dizziness, somnolence, and peripheral edema 
  • When used for epilepsy in adults and children over age 12: Somnolence, dizziness, ataxia, fatigue, and nystagmus 
  • When used for epilepsy in children between age 3 to 12: Viral infection, fever, nausea and/or vomiting, somnolence, and hostility

Severe 

If you experience serious side effects of gabapentin, you should seek urgent medical attention. 

Severe side effects of gabapentin:

Warnings and Interactions

Suddenly stopping gabapentin can trigger a seizure or may result in status epilepticus, which is a type of prolonged seizure that requires medical intervention. This withdrawal effect is more likely if you are taking it for the management of epilepsy. 

If you will stop taking gabapentin, you need to gradually stop the medication as directed by your doctor. And if you have epilepsy, your doctor might prescribe another anticonvulsant to replace your gabapentin as you are decreasing your gabapentin dose. 

Gabapentin can interact with other medications, including:

  • Hydrocodone: Taking gabapentin with hydrocodone decreases the effects of hydrocodone. 
  • Morphine: Taking gabapentin with morphine can cause extreme sleepiness and trouble breathing.
  • Maalox: If you take Maalox, it can reduce the effects of your gabapentin, which could result in pain or seizures (depending on why you are taking gabapentin). It is recommended to avoid taking Maalox within two hours of your gabapentin dose.
Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Horizant label. Updated December 2012.

  2. Food and Drug Administration. Gabapentin label. Updated April 2020.

  3. Goodman CW, Brett AS. A clinical overview of off-label use of gabapentinoid drugs. JAMA Intern Med. 2019;179(5):695-701. doi:10.1001/jamainternmed.2019.0086

  4. Pauly NJ, Delcher C, Slavova S, Lindahl E, Talbert J, Freeman PR. Trends in gabapentin prescribing in a commercially insured U.S. adult population, 2009-2016. J Manag Care Spec Pharm. 2020;26(3):246-252. doi:10.18553/jmcp.2020.26.3.246