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.
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.
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. 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 right away 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 very serious side effects, including: slow/shallow breathing. 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: fever, swollen lymph nodes, 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 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
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.
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. A product that may interact with this drug is: orlistat. Tell your doctor or pharmacist if you are using other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine). 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.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness, slurred speech, weakness.