Gabapentin Common Side Effects: What Are They?
Gabapentin is in a class all its own. The medication belongs to a class of drugs named after itself called gabapentinoids. Besides inventing its own class of medications, gabapentin has also revolutionized the treatment of several other conditions, including various types of nerve pain, called neuropathy. While originally intended to treat seizures when used in combination with other anticonvulsants, today, gabapentin is mainly used to treat numerous other conditions for which it has been proven effective. Although originally considered safe and non-habit forming, doctors have seen a rise in gabapentin abuse in conjunction with the opioid epidemic, as addicts combine narcotics with gabapentin in order to enhance the effects of their high. Today, regulations around gabapentin are changing in many states as governments try their best to prevent abuse of the medication. Gabapentin can certainly be a miracle drug for certain types of pain, but it also comes with a long list of side effects, some of which can be serious.
What is Gabapentin?
Gabapentin is an anti-epileptic/anticonvulsant prescription drug that belongs to its own class of drugs called Gabapentinoids. The medication is similar in chemical structure to the brain chemical GABA, which affects the body’s nervous system. Gabapentin is the generic form of brand name drugs including Gralise, Horizant, and Neurontin, each of which has specific applications and uses. The drug was first approved by the Food and Drug Administration in late 1993 on the brand name Neurontin for the purpose of controlling seizures when used in conjunction with other anticonvulsants. Today, however, gabapentin is used to treat a wide variety of non-epileptic conditions; approximately 83 percent of gabapentin prescriptions are written to treat something other than epilepsy.
What is Gabapentin Used to Treat?
In general, gabapentin is used to treat several conditions, including focal seizures, neuropathic pain, including neuropathic pain caused by the herpes virus or shingles, and restless legs syndrome. However, gabapentin is marketed under several different brand names, each of which treats specific conditions. A brief description of each of the conditions treated by gabapentin and their symptoms is noted below.
Focal seizures, also known as partial seizures, are seizures that occur only in one part of the brain. Focal seizures can either be classified as simple, in which the individual remains conscious throughout the seizure and can remember it when it is over, or complex, in which the individual loses consciousness during the seizure and has no memory of it when it is over. Symptoms known to occur during focal seizures include:
- Muscle contractions
- Odd sensations
- Abnormal head or eye movements
- Automatisms (repetitive movements) such as skin-picking or lip-smacking
- Vision changes (double vision)
- Prior to experiencing a focal seizure, some people experience a sensation known as an aura. During an aura, a person perceives a light or smell and has a confusing feeling just prior to a seizure. Bystanders may notice symptoms such as staring, rapid eye blinking, or stiffening of the body, followed by confusion or exhaustion.
In general terms, neuropathy is described as pain associated with damage to the nerves outside of the brain and spinal cord. When these nerves are damaged, you may experience numbness or weakness in your extremities or other parts of your body, known as peripheral neuropathy. Neuropathic pain is often not relieved by painkillers such as nonsteroidal anti-inflammatory drugs (NSAIDs), opioid pain medication, or other types of pain medicine. Gabapentin is used to treat certain types of neuropathy, including postherpetic neuralgia, a type of pain caused by nerve damage due to shingles. Shingles is a disease affecting adults that results from the same virus that causes chicken pox, and it causes a painful rash. Gabapentin may also be used to treat diabetic neuropathy, or nerve pain resulting from damage to the nerves caused by high blood sugar, as well as other types of nerve pain.
Restless Legs Syndrome
Restless legs syndrome, also known as Willis-Ekborn disease, causes an uncontrollable urge to move your legs due to uncomfortable feelings in your legs. Restless legs syndrome can begin at any age and typically affects people in the evening or nighttime hours when they are sitting or lying down, which can lead to a disruption of sleep. People with restless legs syndrome feel temporary relief of uncomfortable sensations when they move their legs, either by stretching, jiggling their legs, pacing, or walking. The sensations associated with restless leg syndrome have been described as crawling, creeping, pulling, throbbing, aching, itching, and electric.
How Does Gabapentin Work?
Gabapentin works by impacting the way the nerves send messages to the brain. Sometimes, due to damage or malfunction, nerves send false messages to the brain, causing the brain to think that a part of the body is in pain. Gabapentin binds strongly to a specific site on voltage-gated calcium channels in the brain, which helps to relieve the body of pain and prevent seizures.
What is the Cost of Gabapentin?
Because gabapentin is a generic medication, it is generally affordable and accessible, even for the 80 million Americans who are uninsured or underinsured. However, it is important to note that not all generic forms of gabapentin are interchangeable with the branded versions, as some of the branded versions treat only selected conditions. Name brand versions of the drug, including Neurontin, are considerably more expensive. Gabapentin is covered by many private insurance companies, as well as Medicare. The costs for a 30-day supply of Neurontin are compared to the costs for a 30-day supply of gabapentin below.
Costs of a 30-Day Supply of Neurontin and Gabapentin
100 mg oral capsules
300 mg oral capsules
400 mg oral capsules
While some people are concerned about taking the generic forms of medication, the FDA subjects generic drugs to the same stringent testing as the brand name form of the drug. The generic medication uses the same active ingredient as the brand name form of the medication in the same amount, but may use different inactive ingredients that affect the color, size, shape, or taste of the medication. However, you will receive the same treatment when using a generic medication of the same form and strength as you would with a brand name medication.
What Are the Benefits of Using Gabapentin?
Gabapentin is an effective, affordable, accessible medication with numerous helpful applications. Benefits of using gabapentin include:
There are no existing studies that indicate specific issues resulting from use in children. Children as young as three can take gabapentin safely.
There are no existing studies that demonstrate specific issues resulting from use in the elderly.
Gabapentin is available from numerous manufacturers and is affordable and accessible for most people.
How Do I Know What Dose of Gabapentin to Take?
The dose of gabapentin that your doctor prescribes will depend on your age and the condition being treated, among other factors.
Treatment of Seizures
When used to treat seizures, adults and children twelve years of age and older will start by taking 300 mg three times per day, with the dosage adjusted as needed by a doctor. The maximum dosage per day is 2400 mg per day. Children between the age of three and eleven will have their dose based on body weight, with the starting dose being ten to fifteen mg per kg of body weight per day, divided into three doses.
Adults treating their neuropathy with gabapentin will start with a dose of 300 mg taken as a single dose each day. The dose may be adjusted by a doctor as needed to control pain, but should not exceed more than 1800 mg per day except in exceptional circumstances.
What Are the Possible Side Effects of Gabapentin?
Side effects associated with gabapentin generally fall into two categories: side effects requiring medical attention and side effects that do not require medical attention. Side effects requiring medical attention include:
- Clumsiness or unsteadiness
- Continuous uncontrollable eye movements
- Black tarry stools
- Chest pain
- Depression, irritability, or other mood or mental changes
- Loss of memory
- Pain or swelling in the extremities
- Painful or difficult urination
- Trouble breathing
- Sore throat
- Sores, ulcers, or white spots on the lips or in the mouth
- Swollen glands
- Unusual bleeding or bruising
- Unusual tiredness or weakness
- Aggressive behavior in children
- Anxiety in children
- Concentration issues in children
- Crying in children
- Depression in children
- False sense of security in children
- Hyperactivity or increase in body movements in children
- Rapidly changing moods in children
- Overreacting/overly emotional in children
- Restlessness in children
- Distrust in children
Side effects not requiring medical attention include, but are not limited to:
- Blurred vision
- Cold or flu-like symptoms
- Lack or loss of strength
- Lower back or side pain
- Swelling of the hands, feet, or lower legs
- Trembling or shaking
- Accidental injury
- Increased appetite
- Back pain
- Bloated or full feeling
- Body aches or pain
- Burning, itching or dry eyes
- Change in vision
- Change in walking or balance
- Clumsiness or unsteadiness
- Viral infection
- Nausea and vomiting
- Trouble speaking
- Jerky movements
Are There Any Risks Associated With Gabapentin?
The primary risk associated with use of gabapentin is the possibility of abuse of the medication. People who are already addicted to opioids or other drugs are more likely to abuse gabapentin, which is said to produce a calm or euphoric effect similar to the high received from marijuana.
Signs of gabapentin abuse include:
- Coordination problems
- Suicidal thoughts or behaviors
- Changes in mood
- Poor coordination
- Difficulty speaking
- Inability to feel pleasure
People who take gabapentin are at an increased risk of experiencing suicidal thinking, ideation, and behavior. Talk to your doctor if you notice any significant changes in your mood or behavior.
Gabapentin can impact your ability to think and react quickly, and it can cause drowsiness or dizziness. You should not drive or operate heavy machinery until you know how gabapentin makes you feel.
Rarely, gabapentin can cause a reaction called multiorgan hypersensitivity, or drug reaction with eosinophilia and systemic symptoms (DRESS), which can be life-threatening. Seek medical attention immediately if you experience symptoms such as a rash, fever, or swollen lymph nodes.
The effects of gabapentin can be exacerbated by alcohol, so you should not consume alcohol while taking this medicine. Gabapentin causes sleepiness in some individuals, which is enhanced by alcohol. Alcohol can also cause feelings of dizziness and trouble concentrating when combined with gabapentin.
People with seizures should not stop taking gabapentin suddenly, as this can increase the risk of experiencing a condition called status epilepticus, which causes short or long seizures lasting for 30 minutes or more and is considered a medical emergency. Children between the ages of three through twelve may experience behavioral changes when taking gabapentin to control their seizures.
People with kidney problems should use caution when taking gabapentin, as your kidneys may not be able to process gabapentin efficiently enough, causing levels of the medication in your body to be unsafe. If you have kidney problems, make sure to talk to your doctor about your medical history prior to taking gabapentin.
Is Gabapentin Safe for Pregnant and Nursing Women?
Gabapentin is currently classified by the FDA as a Category C medication for pregnant women, meaning that not enough research has been done on the effects of gabapentin in pregnant women to determine conclusively if risk to the fetus may occur. Studies on laboratory animals have shown adverse effects in pregnancy; however, studies on animals do not always translate directly to similar impacts to humans. If you take gabapentin to manage seizures, your doctor may decide to keep you on the mediation if the benefits outweigh the risks. Generally, gabapentin should only be taken during pregnancy if it is needed to manage a serious health condition.
Because gabapentin can transfer through breast milk to nursing infants, nursing women should not take the medication. Gabapentin can cause serious side effects in a nursing child. Women who are nursing should monitor their newborns for symptoms including drowsiness, poor weight gain, and developmental issues if they continue to take the medication while nursing.