Introduction

Gabapentin, sold under the brand names Neurontin and Gralise, is essentially a relaxant for your brain, calming certain neurotransmitters and abnormal brain activities that can cause seizures or nerve pain from shingles (postherpetic neuralgia). As an anticonvulsant, doctors often prescribe it for epilepsy, and sometimes off-label for diabetic neuropathy, mood disorders, and alcohol withdrawal. The downside? Like most medications, it comes with the risk of side effects.

Fortunately, these effects often subside as your body gets used to the drug, although that that timeframe depends on the person. Read on for more information on gabapentin’s side effects and their duration.

How long do gabapentin side effects last?

Introducing your body and brain to a new drug can be a bumpy ride for some. Since you’re not accustomed to the drug, you may experience side effects right off the bat. For example, clinical trials showed that 19% of epilepsy patients taking gabapentin experienced somnambulance, while 17% had dizziness, 13% had ataxia, and 11% felt fatigue.

However, in many cases, these side effects don’t last forever—just as long as it takes for your body to adjust. According to Dr. Alex Dimitriu, MD, founder of Menlo Park Psychiatry & Sleep Medicine, “most side effects are because it is sedating, and these can include dizziness, sleepiness, fatigue, all of which generally improve within days or up a few weeks from starting.”

The National Capital Poison Center agrees, saying side effects can last anywhere from several days to a few weeks. It depends on your body’s tolerance, your dosage, and your condition.

Other common side effects of gabapentin include:

• Drowsiness

• Swelling of the extremities

• Uncontrolled eye movements

• Tremors

• Weakness

• Diarrhea

• Dry mouth

• Sore throat

• Cough

• Constipation

• Nausea

• Vomiting

• Loss of coordination

• Blurred or double vision

• Lazy eye

• Abnormal thinking

• Weight gain

• Slurred speech

• Memory problems

• Depression

• Upset stomach

Children are more likely than adults to get gabapentin side effects, and they may also experience mood swings, hostility, hyperactivity, and infection.

Managing gabapepntin side effects

If your side effects don’t go away within a couple of weeks, the prescribing doctor may want to reduce your dosage, which could help you feel better. But your dose of gabapentin isn’t the issue, you don’t just have to grin and bear it. There are still ways you can help avoid or manage your adverse effects. They include:

• Take the correct dose: Don’t stray from your doctor’s directions, skip doses, or take more than you’re supposed to. Doctors may start slow, because “starting at a very low dose (100-300mg) and gradually increasing this dose also help reduce side effects,” Dr. Dimitriu says.

• Take gabapentin with food: This may help with nausea, upset stomach, or vomiting.

• Take antacids and gabapentin at least two hours apart: Antacids change how the body absorbs gabapentin, potentially causing side effects.

• Avoid alcohol: Drinking can increase the drowsiness, dizziness, impairment, and other nervous system symptoms you might experience with gabapentin.

• Stay hydrated: Sometimes, gabapentin can cause dry mouth and mild dehydration, especially if it causes vomiting, so staying hydrated is key.

• Avoid other sedative medications or supplements: Prescription drugs like opioids, over-the-counter medications like antihistamines, and supplements like valerian or melatonin can make the sedation from gabapentin more pronounced, causing impairment.

For some serious side effects, however, at-home management won’t cut it. If you experience breathing problems, suicidal thoughts, hallucinations, problems speaking or swallowing, or signs of an allergic reaction, seek medical help ASAP.

How long do the side effects of gabapentin withdrawal last?

The Drug Enforcement Agency hasn’t classified gabapentin as a controlled substance at the federal level, but certain state governments have. Even though it’s effective in treating withdrawal for alcohol and some other drugs, there have been numerous case reports of gabapentin abuse, misuse, and physical dependence. And where there’s a risk for addiction, there’s a risk of withdrawal.

“Gabapentin withdrawal can last 1-2 weeks, but will also depend on how quickly the medicine is stopped,” Dr. Dimitriu says, which is why doctors often say to avoid going cold turkey.

“If you have been taking gabapentin for a while, I suggest slowly tapering off the medication rather than abruptly stopping. This is particularly important if you have been taking a higher dose,” says Dr. David Hendricks, MD, assistant medical director at Mountainside. “I advise working with your healthcare provider to begin taking lower doses of the medication until you can safely stop.”

Most patients who experience withdrawal see symptoms arise between 12 hours and seven days after their last dose of gabapentin. According to the American Addiction Centers, gabapentin withdrawal symptoms can include:

• Anxiety

• Agitation

• Insomnia

• Fatigue

• Restlessness

• Irritability

• Dizziness

• Headache

• Sensitivity to light

• Sweating

• Irregular heartbeat

• Nausea

Gabapentin withdrawal syndrome isn’t the same for everyone, though. Factors that may influence it include the dosage, the length of use, the condition being treated, other health conditions, and the cocurrent use of alcohol or other drugs.

Navigating gabapentin withdrawal

Anyone who’s considering stopping their gabapentin treatment should talk to a doctor before anything else. They can draw up a plan, based on the patient’s specific circumstances, that will reduce the risk of withdrawal symptoms.

This plan will usually involve tapering off the drug, although the tapering timeline can vary. “The exact length and severity of these side effects depends on how much gabapentin you were consuming each day and how long you have been using the substance,” Dr. Hendricks says. “Two weeks after quitting, the uncomfortable side effects should dissipate, however the anxiety may be prolonged.” The drug’s prescribing information recommends tapering off over at least one week, although some patients may need multiple weeks or even months, depending on their healthcare provider’s assessment.

How to best manage withdrawal symptoms depends on which symptoms you’re experiencing. Sometimes, the doctor might prescribe other medications—like anti-anxiety drugs, sleep aids, or anti-nausea drugs. And in cases of psychological symptoms, therapy or support groups might work well. Living a generally healthy lifestyle by getting enough sleep, eating a healthy diet, staying hydrated, and exercising regularly may also help. These habits might not cure your withdrawal, but they can go a long way.

Certain cases of severe gabapentin addiction or withdrawal may require a detox at a recovery clinic. These cases are rare, but it’s important to get professional help if you struggle with addiction or think you might relapse.

Important note: If you’re struggling with gabapentin dependence or withdrawal, the Substance Abuse and Mental Health Services Administration (SAMHSA) has a free helpline available 24/7/365. They can help you find local addiction treatment centers, support groups, and other assistance.

The bottom line

If looking at the list of potential gabapentin side effects is making you think twice about taking it, know that not everyone experiences them. And even if you do, they’re typically only temporary—lasting several days or so. Getting medical advice from healthcare professionals ahead of time, however, is essential to a safe and effective gabapentin treatment. Your doctor will develop a treatment plan that fits your condition, medical history, and other circumstances. And if you ever need to stop taking it, they can help you taper off safely, reducing the risk of withdrawal.  

Key takeaways

• Gabapentin is an anticonvulsant medication that’s FDA-approved to treat partial seizures from epilepsy, nerve pain, and restless leg syndrome. Some doctors may also prescribe it for off-label uses like anxiety, depression, or alcohol withdrawal.

• Gabapentin may cause any number of common side effects, but they typically only last until the body adjusts to the drug.

• Although the federal government doesn’t classify gabapentin as a controlled substance, some states do because it has been associated with abuse, dependency, and withdrawal.

• Gabapentin withdrawal symptoms often show up within 12 hours to seven days of the last dose, and usually last for around ten days. This is why doctors will have patients taper off the drug.

Sources

• Gabapentin label, U.S. Food and Drug Administration

• Neurontin (gabapentin): side effects, interactions, and overdose, National Capital Poison Center

• Neurontin side effects: How do I manage them?, Mayo Clinic (2022)

• Efficacy of gabapentin for the treatment of alcohol use disorder in patients with alcohol withdrawal symptoms, JAMA Internal Medicine (2020)

• Gabapentin: abuse, dependence, and withdrawal, Annals of Pharmacotherapy (2015)

• Gabapentin withdrawal symptoms, signs, and side effects, American Addiction Centers (2024)