What is Neurontin?
Neurontin (gabapentin) is an anti-epileptic medication, also called an anticonvulsant. It affects chemicals and nerves in the body that are involved in the cause of seizures and some types of pain.
Neurontin is used to treat partial seizures in adults and children who are at least 12 years old.
It is also used to treat nerve pain associated with herpes zoster (shingles) in adults.
Neurontin may be used as part of a combination therapy. That means you need to take it with other drugs. Neurontin is used to treat seizures caused by:
Partial seizure (a type of seizure that affects only one part of the brain)
Gabapentin is an anticonvulsant medication used to prevent seizures. Gabapentin is also used to relieve nerve pain following shingles (herpes zoster) in adults. Gabapentin EN (GPT-300), Horizant (gabapentin enacarbil), and Fanatrex (fosphenytoin sodium) are oral drugs used to treat partial seizures in adults.
Gabapentin may also be used for purposes not listed in this medication guide.
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, depression, trouble sleeping, or if you feel agitated, irritable, hostile, aggressive, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have:
Signs of a serious allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Drowsiness, dizziness, tired feeling;
slurred speech, problems with coordination;
blurred vision, eye pain, or seeing halos around lights;
swelling in your hands, ankles, or feet;
depression, confusion, unusual thoughts or behavior; or
any type of skin rash.
Common side effects may include:
headache; diarrhea, constipation; blurred vision; or
feeling anxious or irritable.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
The recommended starting dose of Neurontin for partial seizures in children ages 3-12 is 10-15 mg/kg per day given in two or three divided doses. The effective dose range is 20-40 mg/kg/day.
The recommended starting dose of Neurontin for postherpetic neuralgia is 300 mg taken three times a day on Day 1, then increased to 600 mg taken three times a day on Day 2. If needed, the dose can be increased to 1800 mg taken three times a day on Day 3.
If you take an antacid that contains aluminum or magnesium, wait at least 2 hours before taking gabapentin.
Gabapentin may interact with other medications. Tell your doctor all prescription and over-the-counter medications and supplements you use. During pregnancy, Neurontin should be used only when prescribed. This medication passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breastfeeding.
Mechanism of Action
The precise mechanism of action of gabapentin is unknown. However, it is believed to work by inhibiting the release of certain neurotransmitters in the brain that are responsible for seizures and pain.
Gabapentin is structurally related to the neurotransmitter gamma-aminobutyric acid (GABA) but does not interact directly with GABA receptors. It is thought that gabapentin binds to a specific site on calcium channels which leads to its inhibitory activity. This action may be responsible for its anticonvulsant and analgesic (pain relieving) effects.
Gabapentin is rapidly and almost completely absorbed from the GI tract following oral administration. Peak plasma concentrations are achieved within 2-3 hours.
Gabapentin is not appreciably metabolized in humans. Less than 2% of a dose is excreted as unchanged drug in the urine.
The elimination half-life of gabapentin is 5 to 7 hours and is unaltered by age or renalfunction.
Alternatives to Neurontin
Other drugs that have been used to treat partial seizures or postherpetic neuralgia include:
carbamazepine (Tegretol, Equetro, Carbatrol);
phenytoin (Dilantin, Phenytek);
valproic acid (Depakene, Depakote); and