What is Gabapentin?

Gabapentin pills and tablets, medicine
Gabapentin is available in a wide variety of forms. (Image credit: National Library of Medicine)

Gabapentin, or Neurontin, is an anticonvulsant with analgesic properties that is available in capsule, tablet and oral solution. It has a wide range of intended uses, including controlling specific types of seizures in patients with epilepsy, treating postherpetic neuralgia (PHN) and restless leg syndrome.

In the treatment of seizures, gabapentin decreases abnormal activity in the brain, specifically excitement. When treating PHN, which is the lingering pain after suffering shingles, gabapentin changes the way the body senses pain, lowering the burning, aching and stabbing pain that can last up to years after a diagnosis. However, it is unknown exactly how it works in the treatment of restless legs syndrome.

Gabapentin can also be used to as a pain reliever for those suffering from diabetic neuropathy, which is numbness or pain due to diabetes and subsequent nerve damage. For menopausal women or women being treated for breast cancer, gabapentin can relieve hot flashes. It has also proven as an effective treatment for those suffering from alcohol dependency. In a recent study, patients who received high doses of gabapentin were four times more likely to stop drinking altogether, and twice as likely to refrain from heavy drinking. It is the only medication to have shown to help the alcohol dependent sleep better and improve their moods.

Dosage

Due to the nature of the medication, it is recommended that this drug be taken at specific timed intervals throughout the day. Medline Plus recommends that no more than 12 hours should pass between each dose. The extended-release tablet, however, should be taken once a day at 5 pm with food. Medline Plus warns against using extended-release tablets as a substitution for other capsules, unless directed by a doctor.

If being used to treat seizures or PHN, dosage will likely start low and then be increased as needed to treat the condition. Pharmacists for the VA recommend starting at 300 mg a day, and increasing on a specific schedule until up to 3600 mg a day. It is important to continue to take the medication as directed, and not stop abruptly. Sudden withdrawal can cause seizures in patients taking gabapentin for seizures. Even for patients without epilepsy, abrupt discontinuation can cause withdrawal symptoms. Withdrawal can cause disorientation, tachycardia, hostility, and abdominal problems.

However, some people try to self-medicate when dealing with cocaine or alcohol addiction, and end up taking gabapentin to ease their anxieties and develop a high. Like all medications, these drugs should be administered only by a medical professional, as tolerances develop and abusers need to increase their doses more and more. Overdoses are not common, but can cause drowsiness, ataxia, nausea and vomiting, tachycardia, and hypotension.

Some drugs, including antacids and painkillers, can cause drug interactions. The VA recommends letting your doctor know if you are taking antacids, hydrocodone, morphine, naproxen, felbamate, or phenytoin. Gabapentin should be taken at least two hours after antacids, as they can reduce the efficacy of the drug.

Side effects

Gabapentin comes with a number of side effects. According to Medline Plus, gabapentin can cause drowsiness or clumsiness. It can cause dizziness, headaches, uncontrollable shaking, vision problems, memory problems, nausea, vomiting, diarrhea, weight gain, and joint swelling. It can also cause mental health changes, including suicidal thoughts. Medline Plus recommends alerting a doctor if you suffer rash, itching, swelling of the face, difficulty breathing, or seizures.

The use of gabapentin in children, age 3-12, can cause adverse psychiatric events, according to the FDA. Children can develop behavioral problems, hostility, concentration problems, and hyperactivity.

Gabapentin for dogs and cats

For dogs and cats, gabapentin can be used to treat chronic pain, and is usually combined with other analgesic agents, like NSAIDs. It can also be used for dogs and cats with epilepsy, as well as horses who may suffer seizures due to hypoxic ischemic encephalopathy. Side effects include sedation and ataxia. For pets, gabapentin should be used in caution for animals with decreased liver or renal function. Much like in humans, the medication should not be discontinued abruptly.

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