Gabapentin is a prescription medication known as a gamma aminobutyric acid (GABA) analogue. GABA reduces the excitability of nerve cells (neurons) in the brain, which play a role in seizures and the transmission of pain signals. Gabapentin mirrors the effects of GABA calming excited neurons.
Gabapentin is in a class of medications called anticonvulsants.
What are the brand names of gabapentin?
Gabapentin is available as both a brand name product and a generic product (chemically the same, usually lower cost than the brand name product). Brand names of gabapentin include Horizant®, Gralise® and Neurontin®.
What is gabapentin approved for?
Gabapentin is used to:
- Prevent and control partial seizures. Gabapentin can be used in adults and children age 3 and older who have partial seizures.
- Relieve nerve pain following shingles in adults. Shingles is a painful rash that develops many years after you’ve had chickenpox. The virus that causes chickenpox stays dormant in a portion of your spinal nerve root called the dorsal root ganglion. For whatever reason, this otherwise dormant virus gets reactivated — usually by stress — causing a shingles rash. Nerve pain following a case of shingles is called postherpetic neuralgia (PHN).
- Treat moderate-too-severe primary restless legs syndrome.
The branded gabapentin products Neurontin and Gralise are approved for partial seizures and PHN. The branded gabapentin enacarbil product Horizant is approved for restless legs syndrome and PHN.
Read the Medication Guide and, if available, the Patient Information Leaflet provided by your pharmacist before you start taking gabapentin and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take this medication by mouth with or without food as directed by your doctor. Dosage is based on your medical condition and response to treatment. For children, the dosage is also based on weight.
If you are taking the tablets and your doctor directs you to split the tablet in half, take the other half-tablet at your next scheduled dose. Discard half tablets if not used within several days of splitting them. If you are taking the capsules, swallow them whole with plenty of water.
It is very important to follow your doctor’s dosing instructions exactly. During the first few days of treatment, your doctor may gradually increase your dose so your body can adjust to the medication. To minimize side effects, take the very first dose at bedtime.
Take this medication regularly to get the most benefit from it. This drug works best when the amount of medicine in your body is kept at a constant level. Therefore, take gabapentin at evenly spaced intervals at the same time(s) each day. If you are taking this medication 3 times a day to control seizures, do not let more than 12 hours pass between doses because your seizures may increase.
Do not take this medication more often or increase your dose without consulting your doctor. Your condition will not improve any faster and the risk of serious side effects may increase.
Do not stop taking this medication without consulting your doctor. Some conditions may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased.
Antacids containing aluminum or magnesium may interfere with the absorption of this medication. Therefore, if you are also taking an antacid, it is best to take gabapentin at least 2 hours after taking the antacid.
Different forms of gabapentin (such as immediate-release, sustained-release, enacarbil sustained-release) are absorbed in the body differently. Do not switch from one form to the other without consulting your doctor.
Tell your doctor if your condition does not improve or if it worsens.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
GABAPENTIN – ORAL
(gab-uh-PEN-tin)
COMMON BRAND NAME(S): Neurontin
USES: Gabapentin is used with other medications to prevent and control seizures. It is also used to relieve nerve pain following shingles (a painful rash due to herpes zoster infection) in adults. Gabapentin is known as an anticonvulsant or antiepileptic drug.
OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional. Gabapentin may also be used to treat other nerve pain conditions (such as diabetic neuropathy, peripheral neuropathy, trigeminal neuralgia) and restless legs syndrome.
HOW TO USE: Read the Medication Guide and, if available, the Patient Information Leaflet provided by your pharmacist before you start taking gabapentin and each time you get a refill. If you have any questions, ask your doctor or pharmacist. Take this medication by mouth with or without food as directed by your doctor. Dosage is based on your medical condition and response to treatment. For children, the dosage is also based on weight. If you are taking the tablets and your doctor directs you to split the tablet in half, take the other half-tablet at your next scheduled dose. Discard half tablets if not used within several days of splitting them. If you are taking the capsules, swallow them whole with plenty of water. It is very important to follow your doctor’s dosing instructions exactly. During the first few days of treatment, your doctor may gradually increase your dose so your body can adjust to the medication. To minimize side effects, take the very first dose at bedtime. Take this medication regularly to get the most benefit from it. This drug works best when the amount of medicine in your body is kept at a constant level. Therefore, take gabapentin at evenly spaced intervals at the same time(s) each day. If you are taking this medication 3 times a day to control seizures, do not let more than 12 hours pass between doses because your seizures may increase. Do not take this medication more often or increase your dose without consulting your doctor. Your condition will not improve any faster and the risk of serious side effects may increase. Do not stop taking this medication without consulting your doctor. Some conditions may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased. Antacids containing aluminum or magnesium may interfere with the absorption of this medication. Therefore, if you are also taking an antacid, it is best to take gabapentin at least 2 hours after taking the antacid. Different forms of gabapentin (such as immediate-release, sustained-release, enacarbil sustained-release) are absorbed in the body differently. Do not switch from one form to the other without consulting your doctor. Tell your doctor if your condition does not improve or if it worsens.
SIDE EFFECTS: Drowsiness, dizziness, loss of coordination, tiredness, blurred/double vision, unusual eye movements, or shaking (tremor) may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if any of these unlikely but serious side effects occur: swelling of the hands/ankles/feet, signs of infection (such as fever, cough, persistent sore throat). A small number of people who take anticonvulsants for any condition (such as seizures, bipolar disorder, pain) may experience depression, suicidal thoughts/attempts, or other mental/mood problems. Tell your doctor immediately if you or your family/caregiver notice any unusual/sudden changes in your mood, thoughts, or behavior including signs of depression, suicidal thoughts/attempts, thoughts about harming yourself. Get medical help right away if you have any serious side effects, including: unusual fever, swollen glands, yellowing skin/eyes, unusual tiredness, dark urine, change in the amount of urine, chest pain. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US – Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. In Canada – Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking gabapentin, tell your doctor or pharmacist if you are allergic to it; or to gabapentin enacarbil; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, mental/mood problems (such as depression, thoughts of suicide). This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Limit alcoholic beverages. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Older adults may be more sensitive to the side effects of this drug, especially swelling of the hands/ankles/feet and loss of coordination. Children may be more sensitive to the side effects of this drug, especially mental/mood/behavior changes (such as hostility, problems concentrating, restlessness). During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. Gabapentin passes into breast milk. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: See also How to Use section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval. Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and narcotic pain relievers (such as codeine, morphine). Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely. Do not use this medication with other medications that contain gabapentin (including gabapentin enacarbil). This medication may interfere with certain laboratory tests for urine protein. Make sure laboratory personnel and all your doctors know you use this drug.
OVERDOSE: If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness, slurred speech, weakness.
NOTES: Do not share this medication with others.
MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up. If you take gabapentin 3 times a day to control seizures, do not let more than 12 hours pass between doses because your seizures may increase. Consult your doctor right away if this occurs.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets. Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
MEDICAL ALERT: Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (US), or 1-800-668-1507 (Canada).
Information last revised September 2011. Copyright(c) 2011 First Databank, Inc.
Are there any serious interactions with gabapentin and other medications?
Serious breathing problems can happen if you take gabapentin with drugs that cause severe sleepiness or decreased awareness. Some examples include narcotic opioids, anti-anxiety medicines, antidepressants, and antihistamines. If you are 65 years of age or older and/or have a condition that affects your lungs, such as chronic obstructive pulmonary disease (COPD), there is an increased risk for breathing problems. Watch for increased sleepiness or decreased breathing when you start taking gabapentin or when the dose is increased. Get help right away if you develop breathing problems.
Seek immediate medical attention if these symptoms develop:
- Confusion.
- Unusual dizziness or lightheadedness.
- Slowed, shallow or trouble breathing.
- Unresponsiveness (can’t wake up).
- Bluish-colored or tinted skin, especially on lips, fingers or toes.
What other medications and products can interact with gabapentin?
Products that interact with gabapentin include:
- Alcohol.
- Antihistamine-containing cold, cough and allergy products.
- Certain medicines for anxiety or sleep.
- Certain medicines for depression, such as amitriptyline, fluoxetine and sertraline.
- Certain medicines for seizures, such as phenobarbital and primidone.
- Certain medicines for stomach problems. (Wait two hours after taking aluminum and magnesium-containing antacids before taking gabapentin.)
- General anesthetics, local anesthetics, or muscle relaxants given before surgery.
- Narcotic pain medicines.
Can I drink alcohol while taking gabapentin?
Avoid drinking alcohol while taking gabapentin. Drinking alcohol with gabapentin could increase sleepiness or dizziness.
What else do I need to know about gabapentin?
Never stop taking gabapentin without talking to your healthcare provider first. Stopping gabapentin suddenly can cause serious problems, including increasing your risk of seizures (if you are taking gabapentin to control seizures) or not improving your symptoms (if taking gabapentin for other indications). Also, never change your dose without talking to your provider first. Always take gabapentin exactly as prescribed.
Don’t drive, operate heavy machinery or do other dangerous activities after taking gabapentin until you know how it affects you.
Read the full prescription information leaflet that comes with your medication. Never hesitate to ask your healthcare provider or pharmacist if you have any questions about gabapentin.
What should I tell my healthcare provider before starting gabapentin?
Tell your healthcare provider if you:
- Have lung or breathing problems.
- Have diabetes.
- Have kidney problems or are on dialysis.
- Have or had mood problems, depression, suicidal thoughts or behavior.
- Have a history of drug abuse or alcohol abuse problems.
- Are pregnant, trying to become pregnant or are breastfeeding.
Inform your providers of all medications you take, including prescription and over-the-counter, as well as supplements, vitamins and herbal products.
Can I take gabapentin if I’m pregnant or thinking of becoming pregnant?
It’s unknown if gabapentin can harm your unborn baby. For this reason, talk to your healthcare provider as soon as you know you are pregnant. You and your healthcare provider will determine if you should take gabapentin during your pregnancy or change to a different medication.
Does gabapentin pass into breast milk?
Yes, gabapentin does pass into breast milk. If you are breastfeeding or planning to breastfeed, talk with your healthcare provider about breastfeeding or medication options.
Is gabapentin a narcotic or controlled substance?
Gabapentin is not a narcotic. It’s not classified as a controlled substance in most states. (Kentucky, West Virginia, Michigan, Tennessee, and Virginia have reclassified gabapentin as a Schedule V controlled substance). Gabapentin is not an opioid.
Is gabapentin addictive?
Gabapentin is not addictive, but this doesn’t mean that gabapentin can’t be abused. A small number of studies have reported misuse and abuse of gabapentin.
Does gabapentin cause withdrawal symptoms?
Gabapentin withdrawal symptoms have been reported since the drug was approved. However, the individuals in these reports experienced symptoms after discontinuing higher-than-recommended doses of gabapentin and for uses for which the drug was not approved.
What’s known about gabapentin and overdose?
Overdoses on gabapentin have been reported. Individuals experienced double vision, slurred speech, drowsiness, diarrhea and sluggishness.
What should I do if I miss a dose of gabapentin?
If you forget to take a dose of gabapentin, take it as soon as you remember. If it’s just a few hours before it’s time to take your next dose, take only one dose. Never take more than one dose in an attempt to catch up. If you have any concerns or questions, be sure to call your healthcare provider or pharmacist right away.