Gabapentin (By mouth)

Gabapentin (gab-a-PEN-tin)

Treats seizures and pain caused by shingles.

Brand Name(s):

FusePaq Fanatrex, Gralise, Neurontin

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to gabapentin.

How to Use This Medicine:

Capsule, Liquid, Tablet

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you. If you have epilepsy, do not allow more than 12 hours to pass between doses.
  • Capsule: Swallow the capsule whole with plenty of water. Do not open, crush, or chew it.
  • Gralise® tablet: Swallow the tablet whole . Do not crush, break, or chew it.
  • Neurontin® tablet: If you break a tablet into 2 pieces, use the second half as your next dose. Do not use the half-tablet if the whole tablet has been cut or broken after 28 days.
  • Oral liquid: Measure the oral liquid medicine with a marked measuring spoon, oral syringe, or medicine cup.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Store the Neurontin® oral liquid in the refrigerator. Do not freeze.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can affect how gabapentin works. Tell your doctor if you also using hydrocodone or morphine.
  • If you take an antacid, wait at least 2 hours before you take gabapentin.
  • Do not drink alcohol while you are using this medicine.
  • Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol. Tell your doctor if you are also using lorazepam, oxycodone, or zolpidem.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney problems (including patients receiving dialysis) or lung problems. Tell your doctor if you have a history of depression or mental health problems.
  • This medicine may cause the following problems:
    • Drug reaction with eosinophilia and systemic symptoms (DRESS) or multiorgan hypersensitivity, which may damage the liver, kidney, blood, heart, or muscles
    • Changes in mood or behavior, including suicidal thoughts or behavior
    • Respiratory depression (serious breathing problem that can be life-threatening), when used with narcotic pain medicines
  • Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
  • This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
  • Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Behavior problems, aggression, restlessness, trouble concentrating, moodiness (especially in children)
  • Blistering, peeling, red skin rash
  • Blue lips, fingernails, or skin, chest pain, fast heartbeat, trouble breathing
  • Change in how much or how often you urinate, bloody or cloudy urine
  • Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
  • Fever, chills, cough, sore throat, body aches
  • Problems with coordination, shakiness, unsteadiness, unusual eye movement
  • Rapid weight gain, swelling in your hands, ankles, or feet
  • Rash, swollen or tender glands in the neck, armpit, or groin
  • Unusual moods or behaviors, thoughts of hurting yourself, feeling depressed

If you notice these less serious side effects, talk with your doctor:

  • Dizziness, drowsiness, sleepiness, tiredness

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088


Last Updated: 11/6/2020


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