Gabapentin is a medicine that may be used for the treatment of certain seizure disorders or nerve pain.
Gabapentin (Generic Neurontin ) is used to help control partial seizures (convulsions) in the treatment of epilepsy. This medicine cannot cure epilepsy and will only work to control seizures for as long as you continue to take it.
Gabapentin (Generic Neurontin ) is also used to manage a condition called postherpetic neuralgia, which is pain that occurs after shingles. It’s also taken for nerve pain. Nerve pain can be caused by different illnesses, including diabetes and shingles, or it can happen after an injury.
Gabapentin (Generic Neurontin ) works in the brain to prevent seizures and relieve pain for certain conditions in the nervous system. It is not used for routine pain caused by minor injuries or arthritis. Gabapentin is an anticonvulsant.
Occasionally, gabapentin (Generic Neurontin ) is used to prevent migraine headaches. Gabapentin (Neurontin) and pregabalin (Lyrica) are anticonvulsants and nerve pain medicines which have structural similarities to the inhibitory neurotransmitter GABA.
Gabapentin (Generic Neurontin ) is available only with your doctor’s prescription.
Gabapentin (Generic Neurontin ) is available in the following dosage forms:
Tablet, Extended Release, 24 HR
DOSAGE FORMS AND STRENGTHS of Gabapentin
100 mg: white hard gelatin capsules printed with “PD” on the body and
300 mg: yellow hard gelatin capsules printed with “PD” on the body and “Neurontin/300 mg” on the cap
400 mg: orange hard gelatin capsules printed with “PD” on the body and “Neurontin/400 mg” on the cap
600 mg: white elliptical film-coated scored tablets debossed with “NT” and “16” on one side
Gabapentin 800 mg: white elliptical film-coated scored tablets debossed with “NT” and “26” on one side
Oral solution: 250 mg per 5 mL (50 mg per mL), clear colorless to slightly yellow solution
Gabapentin (Generic Neurontin ) was developed in 1993 and has indications for shingles (‘postherpetic neuralgia’) and partial-onset seizures. It has had a growing popularity in off-label uses for fibromyalgia, pain from a variety of causes, migraine, cocaine withdrawal, anxiety, and insomnia. A related compound, gabapentin encarbil (Horizant), is approved for shingles and restless leg syndrome. Pregabalin was developed in 2004 and is approved for nerve pain from diabetes and spinal cord injuries, fibromyalgia, and adjunctive treatment of partial-onset seizures. Although prescribed off-label for anxiety in the U.S., it is approved for this purpose in the U.K., where it is sometimes called the ‘new Valium’.
Gabapentin is a structural analogue of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) that was first approved for use in the United States in 1993.
It was originally developed as a novel anti-epileptic for the treatment of certain types of seizures – today it is also widely used to treat neuropathic pain.
Gabapentin has some stark advantages as compared with other anti-epileptics, such as a relatively benign adverse effect profile, wide therapeutic index, and lack of appreciable metabolism making it unlikely to participate in pharmacokinetic drug interactions.
It is structurally and functionally related to another GABA derivative, pregabalin.
Experts aren’t sure exactly how gabapentin works, but research has shown that gabapentin binds strongly to a specific site (called the alpha2-delta site) on voltage-gated calcium channels. This action is thought to be the mechanism for its nerve-pain relieving and anti-seizure properties.
Gabapentin enacarbil (brand name Horizant) is a prodrug of gabapentin which has been designed to overcome the limitations of gabapentin, such as poor absorption and a short duration of action. Gabapentin enacarbil is effective for restless legs syndrome (RLS) and postherpetic neuralgia (nerve pain that occurs following Shingles).
Gabapentin belongs to the group of medicines known as anticonvulsants.
The precise mechanism through which gabapentin exerts its therapeutic effects is unclear.
The primary mode of action appears to be at the auxillary α2δ-1 subunit of voltage-gated calcium channels (though a low affinity for the α2δ-2 subunit has also been reported).
The major function of these subunits is to facilitate the movement of pore-forming α1 subunits of calcium channels from the endoplasmic reticulum to the cell membrane of pre-synaptic neurons.
There is evidence that chronic pain states can cause an increase in the expression of α2δ subunits and that these changes correlate with hyperalgesia.
Gabapentin appears to inhibit the action of α2δ-1 subunits, thus decreasing the density of pre-synaptic voltage-gated calcium channels and subsequent release of excitatory neurotransmitters.
It is likely that this inhibition is also responsible for the anti-epileptic action of gabapentin.
There is some evidence that gabapentin also acts on adenosine receptors and voltage-gated potassium channels, though the clinical relevance of its action at these sites is unclear.