When Was Gabapentin Approved by the U.S. Food and Drug Administration (FDA) ?

About Gabapentin

There are many drugs used to treat anxiety. New studies are now showing that Gabapentin has been a successful treatment for individuals who suffer from anxiety. However, there are no randomized controlled trials on the effectiveness of this medication in generalized anxiety disorder (GAD), and there are only a few case reports.

People with GAD who take Gabapentin have shown to be less irritable, reduce the use of alcohol as self-medication, have fewer depression symptoms, feel less anxious anticipating the future, improve in phobic avoidance (going out in public more and experiencing a significant decrease in panic disorder and reduction of panic attacks).

Gabapentin is an anticonvulsant drug that is primarily used to treat seizures and the pain that follows after an episode of shingles. Gabapentin is considered an off-brand drug used to treat anxiety. Neurontin is the most common brand name for Gabapentin, as well as Horizant and Gralise. Gabapentin has shown to help people with sleeping better, as insomnia is a symptom of anxiety.

Side Effects of Gabapentin 

Like all medications, there are several side effects to taking Gabapentin. Side effects that you experience are relative to your personal reaction to the drug. Everyone is different, so you may not experience side effects that others do or don’t. Some side effects can be nausea, vomiting, tremors, dizziness, sleepiness, double vision, loss of control of bodily movements, fluid retention, difficulty speaking, jerky movements, unusual eye movements, double vision, and unsteadiness.

If you begin to experience any of these symptoms, speak with your doctor immediately. Get emergency help if you suspect you are having an allergic reaction like; swelling of your face, lips, tongue, or throat, hives, and difficulty breathing. If you notice that your symptoms are worsening, contact your doctor immediately. You may not notice symptoms until weeks after taking Gabapentin.

Is Gabapentin Approved by the U.S. Food and Drug Administration (FDA) ?

Gabapentin was originally approved by the U.S. Food and Drug Administration (FDA) in December 1993, for use as an adjuvant medication to control partial seizures (effective when added to other antiseizure drugs) in adults; that indication was extended to children in 2000. In 2004, its use for treating postherpetic neuralgia (neuropathic pain following shingles) was approved.

Gabapentin is best known under the brand name Neurontin manufactured by Pfizer subsidiary Parke-Davis. A Pfizer subsidiary named Greenstone markets generic gabapentin.

In December 2004 the FDA granted final approval to a generic equivalent to Neurontin made by the Israeli firm Teva.

Neurontin began as one of Pfizer’s best selling drugs; however, Pfizer has come under heavy criticism and serious litigation for its marketing of the drug.

They face allegations that, behind the scenes, Parke-Davis marketed the drug for at least a dozen supposed uses that the FDA had not approved.

Today it is a mainstay drug for migraines, even though it was not approved for such use in 2004.

What is Gabapentin Used for ?

Gabapentin comes as a capsule, a tablet, an extended-release (long-acting) tablet, and an oral solution (liquid) to take by mouth. Gabapentin capsules, tablets, and oral solution are usually taken with a full glass of water (8 ounces [240 milliliters]), with or without food, three times a day.

These medications should be taken at evenly spaced times throughout the day and night; no more than 12 hours should pass between doses. The extended-release tablet (Horizant) is taken with food once daily at about 5 PM. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take gabapentin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Gabapentin extended-release tablets cannot be substituted for another type of gabapentin product. Be sure that you receive only the type of gabapentin that was prescribed by your doctor. Ask your pharmacist if you have any questions about the type of gabapentin you were given.

Swallow the extended-release tablets whole; do not cut, chew, or crush them.

If your doctor tells you to take one-half of a regular tablet as part of your dose, carefully split the tablet along the score mark. Use the other half-tablet as part of your next dose. Properly dispose of any half-tablets that you have not used within several days of breaking them.

If you are taking gabapentin to control seizures or PHN, your doctor will probably start you on a low dose of gabapentin and gradually increase your dose as needed to treat your condition. If you are taking gabapentin to treat PHN, tell your doctor if your symptoms do not improve during your treatment.

Gabapentin may help to control your condition but will not cure it. Continue to take gabapentin even if you feel well. Do not stop taking gabapentin without talking to your doctor, even if you experience side effects such as unusual changes in behavior or mood. If you suddenly stop taking gabapentin tablets, capsules, or oral solution, you may experience withdrawal symptoms such as anxiety, difficulty falling asleep or staying asleep, nausea, pain, and sweating. If you are taking gabapentin to treat seizures and you suddenly stop taking the medication, you may experience seizures more often. Your doctor may decrease your dose gradually over at least a week.

Your doctor or pharmacist will give you the manufacturer’s patient information sheet (Medication Guide) when you begin treatment with gabapentin and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs) or the manufacturer’s website to obtain the Medication Guide.

Off-label use exposes patients to adverse effects and generally is not supported by evidence.

The only conditions for which gabapentinoid drugs are FDA-approved to manage pain are postherpetic neuralgia (both gabapentin and pregabalin [Lyrica]) and diabetic neuropathy, spinal cord injury, and fibromyalgia (pregabalin only). Nevertheless, use of these drugs has tripled during the past 15 years. This increase likely reflects gabapentinoid use for managing non–FDA-approved pain conditions, in part to avoid opioid use. In this review, researchers identified 34 placebo-controlled randomized trials (with ≈4200 patients) of gabapentinoids for noncancer, non–FDA-approved pain conditions. Most trials’ durations were 4 to 12 weeks.

Results of the review were as follows:

  • Only weak evidence supports use of gabapentin for diabetic neuropathy (only pregabalin is approved for this indication).
  • Minimal evidence supports use of gabapentin for nondiabetic painful neuropathies.
  • Studies of gabapentinoids for managing low back pain or sciatica have been largely negative.
  • Only minimal evidence supports a clinically meaningful benefit of off-label gabapentin use for fibromyalgia (for which pregabalin is approved).
  • Both gabapentin and pregabalin are approved for managing postherpetic neuralgia, but both are used often for acute zoster pain, for which studies have shown no benefit.
  • A small number of studies of gabapentinoid use for other pain syndromes (e.g., traumatic nerve injury, complex regional pain syndrome, burn injury, sickle cell pain) showed no clinically important benefits.

COMMENT

The markedly increased off-label use of gabapentinoids to manage pain has no or limited evidence of benefit. This practice is worrisome, especially given known high rates of side effects, including dizziness, somnolence, and unsteadiness. In addition, the authors note that patients often are prescribed gabapentinoids to avoid opioid use, but such patients sometimes still use opioids, either prescribed or illicit. The combination of gabapentinoids and opioids is associated with excess risk for opioid overdose.

Dr. Brett is an author of this article and is the Editor-in-Chief of NEJM Journal Watch General Medicine; however, he had no role in selecting or summarizing this article.

What Happens if You suddenly Stop Gabapentin?

About Gabapentin

There are many drugs used to treat anxiety. New studies are now showing that Gabapentin has been a successful treatment for individuals who suffer from anxiety. However, there are no randomized controlled trials on the effectiveness of this medication in generalized anxiety disorder (GAD), and there are only a few case reports.

People with GAD who take Gabapentin have shown to be less irritable, reduce the use of alcohol as self-medication, have fewer depression symptoms, feel less anxious anticipating the future, improve in phobic avoidance (going out in public more and experiencing a significant decrease in panic disorder and reduction of panic attacks).

Gabapentin is an anticonvulsant drug that is primarily used to treat seizures and the pain that follows after an episode of shingles. Gabapentin is considered an off-brand drug used to treat anxiety. Neurontin is the most common brand name for Gabapentin, as well as Horizant and Gralise. Gabapentin has shown to help people with sleeping better, as insomnia is a symptom of anxiety.

Treatment with Gabapentin: Important Things to Know Before Taking Gabapentin

Before you start gabapentin therapy, you should have a thorough medical exam to rule out any medical issues. This includes any blood or urine tests. Medical evaluations are important as gabapentin can induce hormonal imbalances. Like any other drug, you should not take gabapentin if you’re allergic to it.

There are side effects—more on that in a minute. But a few of the most important things your doctor will want to find out before prescribing gabapentin is if you have or have had any of the following:

  • Diabetes
  • Drug or alcohol addiction
  • Kidney problems (or if you’re on dialysis)
  • Liver or heart disease
  • Lung disease (see the warning above on respiratory issues)
  • Mood disorders, depression or bipolar; or if you’ve ever thought about suicide or attempted suicide
  • Seizures (unless, of course, you’re taking it for seizures)

You should also know that not enough studies have been done to understand the exact risks of gabapentin if you’re pregnant or breastfeeding.

Side Effects of Gabapentin 

Like all medications, there are several side effects to taking Gabapentin. Side effects that you experience are relative to your personal reaction to the drug. Everyone is different, so you may not experience side effects that others do or don’t. Some side effects can be nausea, vomiting, tremors, dizziness, sleepiness, double vision, loss of control of bodily movements, fluid retention, difficulty speaking, jerky movements, unusual eye movements, double vision, and unsteadiness.

If you begin to experience any of these symptoms, speak with your doctor immediately. Get emergency help if you suspect you are having an allergic reaction like; swelling of your face, lips, tongue, or throat, hives, and difficulty breathing. If you notice that your symptoms are worsening, contact your doctor immediately. You may not notice symptoms until weeks after taking Gabapentin.

What happens if you suddenly stop gabapentin?

It’s important to discuss your concerns about gabapentin first with your doctor or pharmacist before you stop the medication.

You might have certain symptoms if you suddenly stop gabapentin:

  • withdrawal symptoms such as agitation, restlessness, anxiety, insomnia, nausea, sweating, or flu-like symptoms. The risks of withdrawal are higher if you’re taking high doses or have been on gabapentin for longer than 6 weeks. Withdrawal symptoms can start from 12 hours to 7 days after stopping the medication.
  • status epilepticus, which is a rapid cycle of seizure activity so that an individual experiences an almost constant seizure for a period of time
  • irregular heart rate
  • confusion
  • headache
  • tiredness
  • weakness
  • return of nerve pain

 

Gabapentin for Anxiety and the Dosage of Gabapentin for Anxiety

About Gabapentin

There are many drugs used to treat anxiety. New studies are now showing that Gabapentin has been a successful treatment for individuals who suffer from anxiety. However, there are no randomized controlled trials on the effectiveness of this medication in generalized anxiety disorder (GAD), and there are only a few case reports.

People with GAD who take Gabapentin have shown to be less irritable, reduce the use of alcohol as self-medication, have fewer depression symptoms, feel less anxious anticipating the future, improve in phobic avoidance (going out in public more and experiencing a significant decrease in panic disorder and reduction of panic attacks).

Gabapentin is an anticonvulsant drug that is primarily used to treat seizures and the pain that follows after an episode of shingles. Gabapentin is considered an off-brand drug used to treat anxiety. Neurontin is the most common brand name for Gabapentin, as well as Horizant and Gralise. Gabapentin has shown to help people with sleeping better, as insomnia is a symptom of anxiety.

How Gabapentin Is Used to Treat Anxiety Mood Disorders Like Depression

Gabapentin isn’t usually used to treat anxiety alone. More often, it’s given to ease anxiety symptoms for someone who also has depression or bipolar disorder. (Anxiety is common comorbid with depression and bipolar.) The reason is that it may not be effective for just anxiety. A close look comparing seven different clinical trials on how successful gabapentin is for anxiety shows that gabapentin may be better than a placebo to treat generalized anxiety disorder (GAD), but not much better. Results may be slightly more promising for social anxiety disorder.

The clinical trials for treating depression with gabapentin are also pretty lackluster. To date, there are no scientific studies showing it’s effective—either on its own or as part of some other therapy. Still, there is some anecdotal evidence that it’s helpful, especially with patients who don’t seem to improve with more standard antidepressants.

How Gabapentin Is Used to Treat Mixed Bipolar States

More specifically, can it prevent future episodes of mania and depression? Right now, there is no good evidence that gabapentin can be used for treating people with bipolar disorder. High-quality, randomized controlled studies found that gabapentin was not effective.1,2

Gabapentin and Alcohol Use Disorder

Gabapentin may be helpful in treating alcohol use disorder and withdrawal. Between 2004 and 2010, The Veterans Affairs Department conducted a double-blind, placebo-controlled, randomized dose-ranging trial of 150 men and women over 18, struggling with alcohol dependence.3 The results of the study showed that gabapentin (particularly the 1800 mg dosage) was effective in safely treating alcohol dependence and relapse-related symptoms including insomnia, dysphoria, and cravings.

Side Effects of Gabapentin 

Like all medications, there are several side effects to taking Gabapentin. Side effects that you experience are relative to your personal reaction to the drug. Everyone is different, so you may not experience side effects that others do or don’t. Some side effects can be nausea, vomiting, tremors, dizziness, sleepiness, double vision, loss of control of bodily movements, fluid retention, difficulty speaking, jerky movements, unusual eye movements, double vision, and unsteadiness.

If you begin to experience any of these symptoms, speak with your doctor immediately. Get emergency help if you suspect you are having an allergic reaction like; swelling of your face, lips, tongue, or throat, hives, and difficulty breathing. If you notice that your symptoms are worsening, contact your doctor immediately. You may not notice symptoms until weeks after taking Gabapentin.

Gabapentin Dosage for Anxiety

When you are prescribed Gabapentin to treat your anxiety, your doctor will determine the correct dosage necessary for you. Additionally, doctors will usually start with a lower dose of Gabapentin and gradually increase to the dosage that will become their full intake. Gabapentin comes in capsules of 100, 300, and 400 mg. Gabapentin tablets are available in 100, 300, 400, 600, and 800 mg. Do not change your dosage or stop taking your medications without talking to your doctor first. According to MedicineNet, the starting dose for treating anxiety is 0.25-0.5 mg 3 to 4 times daily using immediate-release tablets. The dose may be increased every 3-4 days to a maximum dose of 4 mg daily. The starting dose for treating panic attacks is 0.5 mg 3 times daily.

How Long Does Gabapentin Take to Work for Anxiety

The effectiveness of Gabapentin is different for everyone, again also depending on the severity of your anxiety amongst other factors. The average timeline for effectiveness is about 3 weeks, but it could be sooner or later. It is important to remember that while Gabapentin may be helpful for some, it may not be helpful for you. If you want to consider using Gabapentin, consult your doctor and together you can make the best decisions regarding treating your anxiety.

What is the Side Effects and Interaction of Gabapentin (Neurontin ) ?

Gabapentin is a prescription medicine that’s used to treat partial seizures in adults and children who are at least 3 years old.

More commonly, it’s prescribed for nerve pain that’s caused by herpes-family viruses (for which it is approved by the U.S. Food and Drug Administration) or other causes for which it is prescribed “off-label.”

Gabapentin is in a class of drugs called anticonvulsants. The medicine works by calming excitement in the brain and changing the way your body senses pain.

Different brands of gabapentin are given for specific medical conditions. It’s important that you only take the brand name that your doctor prescribes.

The FDA approved this medicine in 1993.

What is the Side Effects of Gabapentin ?

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

      1. Clumsiness or unsteadiness
      2. continuous, uncontrolled, back-and-forth, or rolling eye movements

More common in children

      1. Aggressive behavior or other behavior problems
      2. anxiety
      3. concentration problems and change in school performance
      4. crying
      5. depression
      6. false sense of well-being
      7. hyperactivity or increase in body movements
      8. rapidly changing moods
      9. reacting too quickly, too emotional, or overreacting
      10. restlessness
      11. suspiciousness or distrust

Less common

      1. Black, tarry stools
      2. chest pain
      3. chills
      4. cough
      5. depression, irritability, or other mood or mental changes
      6. fever
      7. loss of memory
      8. pain or swelling in the arms or legs
      9. painful or difficult urination
      10. sore throat
      11. sores, ulcers, or white spots on the lips or in the mouth
      12. swollen glands
      13. unusual bleeding or bruising
      14. unusual tiredness or weakness

Incidence not known

      1. Abdominal or stomach pain
      2. blistering, peeling, or loosening of the skin
      3. clay-colored stools
      4. coma
      5. confusion
      6. convulsions
      7. dark urine
      8. decreased urine output
      9. diarrhea
      10. difficult or troubled breathing
      11. dizziness
      12. fast or irregular heartbeat
      13. headache
      14. increased thirst
      15. irregular, fast or slow, or shallow breathing
      16. itching or skin rash
      17. joint pain
      18. large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
      19. loss of appetite
      20. muscle ache or pain
      21. nausea
      22. pale or blue lips, fingernails, or skin
      23. red skin lesions, often with a purple center
      24. red, irritated eyes
      25. unpleasant breath odor
      26. vomiting of blood
      27. yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common Side Effects of Gabapentin

      1. Blurred vision
      2. cold or flu-like symptoms
      3. delusions
      4. dementia
      5. hoarseness
      6. lack or loss of strength
      7. lower back or side pain
      8. swelling of the hands, feet, or lower legs
      9. trembling or shaking

Less common or rare

        1. Accidental injury
        2. appetite increased
        3. back pain
        4. bloated or full feeling
        5. body aches or pain
        6. burning, dry, or itching eyes
        7. change in vision
        8. change in walking and balance
        9. clumsiness or unsteadiness
        10. congestion
        11. constipation
        12. cough producing mucus
        13. decrease in sexual desire or ability
        14. dryness of the mouth or throat
        15. earache
        16. excess air or gas in the stomach or intestines
        17. excessive tearing
        18. eye discharge
        19. feeling faint, dizzy, or lightheadedness
        20. feeling of warmth or heat
        21. flushed, dry skin
        22. flushing or redness of the skin, especially on the face and neck
        23. frequent urination
        24. fruit-like breath odor
        25. impaired vision
        26. incoordination
        27. increased hunger
        28. increased sensitivity to pain
        29. increased sensitivity to touch
        30. increased thirst
        31. indigestion
        32. noise in the ears
        33. pain, redness, rash, swelling, or bleeding where the skin is rubbed off
        34. passing gas
        35. redness or swelling in the ear
        36. redness, pain, swelling of the eye, eyelid, or inner lining of the eyelid
        37. runny nose
        38. sneezing
        39. sweating
        40. tender, swollen glands in the neck
        41. tightness in the chest
        42. tingling in the hands and feet
        43. trouble sleeping
        44. trouble swallowing
        45. trouble thinking
        46. twitching
        47. unexplained weight loss
        48. voice changes
        49. vomiting
        50. weakness or loss of strength
        51. weight gain

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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