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Gabapentin (Generic Neurontin ) was developed to treat epilepsy, but it is now used to treat various forms of chronic pain. It works by reducing the number of signals sent through the nerves. If the signals are reduced then the pain will be reduced. Research has shown that Gabapentin can help in treating various types of nerve pain.
Some Research Team performed searches to look for clinical trials where gabapentin was used to treat neuropathic pain or fibromyalgia. They found that 5633 participants had been involved in 37 studies of reasonable quality. They tested gabapentin against placebo for four weeks or more. Studies lasting only one or two weeks are unhelpful when pain can last for years.
Neuropathic pain is pain coming from damaged nerves. It differs from pain messages carried along healthy nerves from damaged tissue (a fall, cut, or arthritic knee). Neuropathic pain is treated by different medicines than pain from damagedtissue. Medicines like paracetamol or ibuprofen are not effective in neuropathic pain, while medicines that are sometimes used to treat depression or epilepsy can be very effective in some people with neuropathic pain. Our understanding of fibromyalgia (a condition of persistent, widespread pain and tenderness, sleep problems, and fatigue) is poor, but fibromyalgia can respond to the same medicines as neuropathic pain.
Gabapentin is helpful for some people with chronic neuropathic pain or fibromyalgia. Gabapentin comes as a capsule, tablet, or solution. You take it by mouth. Gabapentin is available as the brand-name drugs Neurontin, Gralise, and Horizant. It’s also available as a generic drug.
Please remember that we cannot send you Neurontin if the doctor doesnot approve your prescription. Normally it take longer time for doctors to approve your prescription because they only work in week days and work five hours per day. We do suggest you refill your Neurontin in our website but not the first time to buy neurontin online in our website. We like to refill gabapentin ( Generic Neurontin ) for you.
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The dose of gabapentin required varies from person to person. To avoid side effects we build up to the dose gradually. The tables in this leaflet show you how this can be done. Some patients can put their dose up faster than others. We call this faster way the FAST TRACK (see table 1).
If you find you are getting side effects with the fast track way of putting your dose up, you can switch to the SLOWER METHOD. ( see table 2).
Other people will need to put their dose up less quickly over a number of weeks. This is THE SLOWER METHOD (see table 2).
As with any medication it is important to check how well it works. With gabapentin this can be in a few days but for most patients may take 4-8 weeks to assess the full benefit. If you feel you are getting no benefit from this medication please discuss this with your GP or pain specialist.
By Drugs.com, Gabapentin Can be used for a lot of Nerve Pain related health conditions.
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There are totally 1359 reviews on Gabapentin, only eleven reviews are on Epilepsy whereas 1348 reviews are on Gabapentin Off-label usage. The most widely usage of Gabapentin is for Anxiety ( 243 Reviews ), Pain Relief ( 241 Reviews ), Fibromyalgia ( 137 Reviews ), Peripheral Neuropathy (119 reviews ), Bipolar Disorder ( 83 reviews ), Migraine ( 79 reviews), Neuropathic Pain ( 75 reviews ), Hot Flashes (70 reviews ), Restless Legs Syndrome (61 Reviews ) and Insomnia ( 59 reviews). The most effective usage of Gabapentin is for Pruritus and Cough.
Gabapentin is one drug that researchers have studied for preventing migraines. It has a high safety profile and few side effects. This makes it a good option for Migraine prevention. Results from some clinical trials have shown a modest benefit from the use of gabapentin for migraine prevention. However, the American Academy of Neurology (AAN), the organization that provides guidance for the use of drugs to prevent migraines, has stated that there is not enough evidence at this time to support the use of gabapentin for migraine prevention. Healthcare professionals can choose to prescribe gabapentin when other prevention therapies have not worked, however.
The total number of patients treated with NEURONTIN in controlled clinical trials in patients with postherpetic neuralgia was 336, of which 102 (30%) were 65 to 74 years of age, and 168 (50%) were 75 years of age and older. There was a larger treatment effect in patients 75 years of age and older compared with younger patients who received the same dosage. Since gabapentin is almost exclusively eliminated by renal excretion, the larger treatment effect observed in patients ≥ 75 years may be a consequence of increased gabapentin exposure for a given dose that results from an age-related decrease in renal function. However, other factors cannot be excluded. The types and incidence of adverse reactions were similar across age groups except for peripheral edema and ataxia, which tended to increase in incidence with age.
Clinical studies of NEURONTIN in epilepsy did not include sufficient numbers of subjects aged 65 and over to determine whether they responded differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and dose should be adjusted based on creatinine clearance values in these patients.
What form(s) does this medication come in?
100 mg – Each hard gelatin Coni-Snap capsule, with white opaque body and cap printed with “PD” on one side and “Neurontin/100 mg” on the other, contains gabapentin 100 mg.
300 mg – Each hard gelatin Coni-Snap capsule, with yellow opaque body and cap printed with “PD” on one side and “Neurontin/300 mg” on the other, contains gabapentin 300 mg.
400 mg – Each hard gelatin Coni-Snap capsule, with orange opaque body and cap printed with “PD” on one side and “Neurontin/400 mg” on the other, contains gabapentin 400 mg.
600 mg – Each white, elliptical, film-coated tablet with “Neurontin 600” printed on one side contains gabapentin 600 mg.
800 mg – Each white, elliptical, film-coated tablet with “Neurontin 800” printed on one side contains gabapentin 800 mg.
A lethal dose of gabapentin was not identified in mice and rats receiving single oral doses as high as 8000 mg/kg. Signs of acute toxicity in animals included ataxia, labored breathing, ptosis, sedation, hypoactivity, or excitation.
Acute oral overdoses of NEURONTIN up to 49 grams have been reported. In these cases, double vision, slurred speech, drowsiness, lethargy, and diarrhea were observed. All patients recovered with supportive care. Coma, resolving with dialysis, has been reported in patients with chronic renal failure who were treated with NEURONTIN.
Gabapentin can be removed by hemodialysis. Although hemodialysis has not been performed in the few overdose cases reported, it may be indicated by the patient’s clinical state or in patients with significant renal impairment.
NEURONTIN can cause serious side effects including:
1. Suicidal Thoughts. Like other antiepileptic drugs, NEURONTIN may cause suicidal thoughts or actions in a very small number of people, about 1 in 500.
Call a healthcare provider right away if you have any of these symptoms, especially if they are new, worse, or worry you:
- thoughts about suicide or dying
- attempts to commit suicide
- new or worse depression
- new or worse anxiety
- feeling agitated or restless
- panic attacks
- trouble sleeping (insomnia)
- new or worse irritability
- acting aggressive, being angry, or violent
- acting on dangerous impulses
- an extreme increase in activity and talking (mania)
- other unusual changes in behavior or mood
How can I watch for early symptoms of suicidal thoughts and actions?
- Pay attention to any changes, especially sudden changes, in mood, behaviors, thoughts, or feelings.
- Keep all follow-up visits with your healthcare provider as scheduled.
Call your healthcare provider between visits as needed, especially if you are worried about symptoms.
Do not stop taking NEURONTIN without first talking to a healthcare provider.
- Stopping NEURONTIN suddenly can cause serious problems. Stopping a seizure medicine suddenly in a patient who has epilepsy can cause seizures that will not stop (status epilepticus).
- Suicidal thoughts or actions can be caused by things other than medicines. If you have suicidal thoughts or actions, your healthcare provider may check for other causes.
2. Changes in behavior and thinking -Using NEURONTIN in children 3 to 12 years of age can cause emotional changes, aggressive behavior, problems with concentration, restlessness, changes in school performance, and hyperactivity.
3. NEURONTIN may cause serious or life-threatening allergic reactions that may affect your skin or other parts of your body such as your liver or blood cells. This may cause you to be hospitalized or to stop NEURONTIN. You may or may not have a rash with an allergic reaction caused by NEURONTIN. Call a healthcare provider right away if you have any of the following symptoms:
- skin rash
- difficulty breathing
- swollen glands that do not go away
- swelling of your face, lips, throat, or tongue
- yellowing of your skin or of the whites of the eyes
- unusual bruising or bleeding
- severe fatigue or weakness
- unexpected muscle pain
- frequent infections
These symptoms may be the first signs of a serious reaction. A healthcare provider should examine you to decide if you should continue taking NEURONTIN.
We do not sell Gabapentin to all patients!
Normally Gabapentin is suitable for all adult and children bigger than six years old. But you are not allowed to order Gabapentin online especially in our online pharmacies if you have any of following health conditions (But you are OK to order in your local street pharmacies):
- You are younger than 18 years old;
- You have kidney disease;
- Alcohol – you are addictive to alcohol, gabapentin may cause alcohol intolerance;
- diabetes – Gabapentin may affect blood sugar levels, you must find a local doctor to prescribe you Gabapentin.
- kidney disease,liver disease and heart diseases;
- a history of depression, mood disorder, drug abuse, or suicidal thoughts or actions;
- (for patients with RLS) if you are a day sleeper or work a night shift;
- You are breastfeeding mother or you are pregnant;
- have thoughts about suicide.
- If you are allergy to Gabapentin
Stop immediately if you have any thoughts about suicide. Donot order Gabapentin online if you have suicide thoughts. Please go to your doctor to have you completely checked.
We hope you can refill your Gabapentin online using our online pharmacy. You have already checked by your local doctors and they have prescribed you Gabapentin. After your first prescription, you can order in our websites. Our doctors and pharmacists will review your health conditions too and it is much easier for you to understand the gabapentin prescription you are taking.
Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.
Before taking this medicine
You should not use this medication if you are allergic to gabapentin.
To make sure this medicine is safe for you, tell your doctor if you have:
- kidney disease;
- liver disease;
- heart disease; or
- (for patients with RLS) if you are a day sleeper or work a night shift.
Some people have thoughts about suicide while taking this medicine. Your doctor will need to check your progress at regular visits while you are using gabapentin. Your family or other caregivers should also be alert to changes in your mood or symptoms.
FDA pregnancy category C. It is not known whether gabapentin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.
How should I take gabapentin?
Take gabapentin exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.
The Horizant brand of gabapentin should not be taken during the day. For best results, take Horizant withfood at about 5:00 in the evening.
Both Gralise and Horizant should be taken with food.
Neurontin can be taken with or without food.
If you break a Neurontin tablet and take one half of it, take the other half at your next dose. Any tablet that has been broken should be used as soon as possible or within a few days.
Measure liquid medicine with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.
If your doctor changes your brand, strength, or type of gabapentin, your dosage needs may change. Ask your pharmacist if you have any questions about the new brand you receive at the pharmacy.
Do not stop using gabapentin suddenly, even if you feel fine. Stopping suddenly may cause increased seizures. Follow your doctor’s instructions about tapering your dose.
Wear a medical alert tag or carry an ID card stating that you take gabapentin. Any medical care provider who treats you should know that you take seizure medication.
This medication can cause you to have a false positive urine protein screening test. If you provide a urine sample for testing, tell the laboratory staff that you are taking gabapentin.
Store at room temperature away from light and moisture.
Store the liquid medicine in the refrigerator. Do not freeze.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Be sure to take the medicine with food. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid?
This medication may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.
Avoid taking an antacid within 2 hours before or after you take gabapentin. Antacids can make it harder for your body to absorb this medicine.
Drinking alcohol can increase certain side effects of this medicine.
What other drugs will affect gabapentin?
Taking gabapentin with other drugs that make you sleepy or slow your breathing can worsen these effects. Ask your doctor before taking gabapentin with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.
Tell your doctor about all medicines you use, and those you start or stop using during your treatment with this medicine, especially:
- hydrocodone, (Lortab, Vicodin and others);
- morphine (Kadian, MS Contin, Oramorph, and others); or
- naproxen (Naprosyn, Aleve, Anaprox, and others).
This list is not complete and other drugs may interact with gabapentin. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.
In vitro studies were performed to investigate the potential of gabapentin to inhibit the major cytochrome P450 enzymes (CYP1A2, CYP2A6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4) that mediate drug and xenobiotic metabolism, using isoform selective marker substrates and human liver microsomal preparations. Only at the highest concentration tested (171 μg/mL; 1 mM) was a slight degree of inhibition (14% to 30%) observed with isoform CYP2A6. No inhibition was observed with any of the other isoforms tested at gabapentin concentrations up to 171 μg/mL (approximately 15 times the Cmax at 3600 mg/day). Gabapentin is not an inducer of cytochrome P450 enzymes.
At plasma concentrations associated with doses up to 3600 mg/day (Cmax 11.6 μg/mL), the highest recommended daily dose, a metabolically-based interaction between gabapentin and a drug whose clearance is dependent upon the major cytochrome P450 enzymes is unlikely.
Gabapentin is not metabolized to a significant extent in humans and does not interfere with the metabolism of commonly administered antiepileptic drugs. (See DRUG INTERACTIONS, Drug-Drug Interactions – Antiepileptic agents). Gabapentin also shows a low level of binding to plasma proteins (approximately 3%) and is eliminated solely by renal excretion as unchanged drug. (See ACTION AND CLINICAL PHARMACOLOGY). Consequently, there have been few drug interactions described in which the pharmacokinetics of gabapentin or other
co-administered drugs were affected to an appreciable extent.
Gabapentin Drug-Drug Interactions
The drug interaction data described in this subsection were obtained from studies involving healthy adults and adult patients with epilepsy:
There is no interaction between Neurontin (gabapentin) and phenytoin, valproic acid, carbamazepine, or phenobarbital. Consequently, Neurontin may be used in combination with other commonly used antiepileptic drugs without concern for alteration of the plasma concentrations of gabapentin or the other antiepileptic drugs.
Co-administration of single doses of gabapentin (125 mg to 500 mg; N= 48) and hydrocodone (10 mg; N= 50) decreased the Cmax and AUC values of hydrocodone in a dose-dependent manner relative to administration of hydrocodone alone. The Cmax and AUC values for hydrocodone were 2% and 4% lower, respectively, after administration of 125 mg gabapentin and 16% and 22% lower, respectively, after administration of 500 mg gabapentin. The mechanism for this interaction is unknown. Hydrocodone increased gabapentin AUC values by 14%. The magnitude of interaction with higher doses of gabapentin is not known.
A literature article reported that when a 60 mg controlled release morphine capsule was administered 2 hours prior to a 600 mg gabapentin capsule in healthy volunteers (N= 12), mean gabapentin AUC increased by 44% compared to gabapentin administered without morphine. Morphine pharmacokinetic parameter values were not affected by administration of gabapentin 2 hours after morphine in this study. Because this was a single dose study, the magnitude of the interaction at steady state and at higher doses of gabapentin are not known.
In healthy adult volunteers (N= 18), the co-administration of single doses of naproxen sodium capsules (250 mg) and gabapentin (125 mg) increased the amount of gabapentin absorbed by 12% to 15%. Gabapentin did not affect naproxen pharmacokinetic parameters in this study. These doses are lower than the therapeutic doses for both drugs. Therefore, the magnitude of interaction at steady state and within the recommended dose ranges of either drug is not known.
Coadministration of gabapentin with the oral contraceptive Norlestrin® does not influence the steady-state pharmacokinetics of norethindrone or ethinyl estradiol.
Coadministration of gabapentin with an aluminum and magnesium-based antacid reduces gabapentin bioavailability by up to 20%. Although the clinical significance of this decrease is not known, co-administration of similar antacids and gabapentin is not recommended.
A slight decrease in renal excretion of gabapentin observed when it is coadministered with cimetidine is not expected to be of clinical importance. The effect of gabapentin on cimetidine has not been evaluated.
Renal excretion of gabapentin is unaltered by probenecid.
Neurontin is given orally with or without food.
Interactions with herbal products have not been established.
For urinary protein determination the sulfosalicylic acid precipitation procedure is recommended, as false positive readings were reported with the Ames N-Multistix SG® dipstick test, when gabapentin or placebo was added to other anticonvulsant drugs.
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How Gabapentin Works?
Gabapentin has no direct GABAergic action and does not block GABA uptake or metabolism. Gabapentin blocks the tonic phase of nociception induced by formalin and carrageenan, and exerts a potent inhibitory effect in neuropathic pain models of mechanical hyperalgesia and mechanical/thermal allodynia.
Gabapentin binds preferentially to neurons in the outer layer of the rat cortex at sites that are distinct from other anticonvulsants. It is likely that gabapentin acts at an intracellular site as the maximal anticonvulsant effect is achieved 2 h after an intravenous injection of gabapentin in rats. This occurs after the plasma and interstitial fluid concentrations have peaked and reflects the additional time required for intraneural transport.
Several theories have been proposed to explain the cellular mechanism of its anticonvulsant effect. The most favoured theory involves an interaction with an as yet undescribed receptor linked with the l ‐system amino acid transporter protein. Suman Chauhan et al . demonstrated that l ‐amino acids potently inhibited binding of an␣active enantiomer of gabapentin ([3H]gabapentin). This was further supported by Taylor et al . who showed that the potent anticonvulsant, 3‐isobutyl GABA (an analogue of gabapentin) potently and stereoselectively bound to the same receptor. These findings renewed interest in the isolation of the receptor protein that may responsible for this anticonvulsant effect.
Other proposed biochemical events in the central nervous system (CNS) that may explain its anti‐epileptic effect include the increased extracellular GABA concentrations in some regions of the brain caused by an increase in activity of glutamic acid decarboxylase that produces GABA, and a decreased breakdown by GABA decarboxylase. Although a study, using magnetic resonance imaging (MRI) spectroscopy showed a global increase in GABA in the brain after the administration of gabapentin, there is no evidence that gabapentin increases intraneuronal GABA concentrations, binds GABAA or GABAB receptors, or exerts any GABA‐mimetic action.
Other effects of gabapentin have been described but are not considered to play a significant pharmacodynamic role. These include small decreases in the release of monoamine neurotransmitters (dopamine, noradrenaline and serotonin) and the attenuation of sodium‐dependent action potentials (suggesting sodium channel blockade) after prolonged exposure to gabapentin .
The mode of action of gabapentin in the treatment of neuropathic pain has not been fully elucidated. Although early studies indicated that gabapentin had only a central anti‐allodynic effect, gabapentin has been shown to inhibit ectopic discharge activity from injured peripheral nerves . The mechanisms of the anti‐allodynic effects of gabapentin proposed include: CNS effects (potentially at spinal cord or brain level) due to either enhanced inhibitory input of GABA‐mediated pathways (and thus reducing excitatory input levels); antagonism of NMDA receptors; and antagonism of calcium channels in the CNS and inhibition of peripheral nerves. Of these, antagonism of the NMDA receptor and calcium channel blockade have the most supporting evidence. Field et al . discounted an antihyperalgesic action via opioid receptor binding after demonstrating that morphine tolerance does not alter the efficacy of gabapentin and naloxone does not reduce its antihyperalgesic effect.
Research into a peripheral site of action for gabapentin has produced contradictory results. Intrathecal administration of gabapentin blocks thermal and mechanical hyperalgesia without affecting sympathetic outflow or acute nociception, and this suggests a spinal site of action . Patel et al . demonstrated a presynaptic site of action for gabapentin in the rat spinal cord.
Although gabapentin does not bind to GABAA or GABAB receptors, increased synthesis and reduced breakdown of GABA have been described. Potentiation of inhibitory GABA‐ergic pathways seems unlikely to be responsible for its anti‐allodynic effect because GABA receptor antagonists do not reduce this effect .
The NMDA receptor complex is a ligand‐gated ion channel that mediates an influx of calcium ions when activated. The NMDA receptor complex has a number of binding sites for various ligands that regulate its activity, including the strychnine‐insensitive glycine binding site, phencyclidine binding site, polyamine binding site, redox modulatory site and a proton‐sensitive site. Partial depolarisation of the neuron after glutamine activation will release a magnesium plug and allow calcium influx into the neuron. These receptors are known to be found in high concentrations in the hippocampus and have been attributed a key role in the process of central sensitisation of painful stimuli, commonly known as the ‘wind‐up’ phenomenon, leading to hyperalgesia. Evidence linking gabapentin to the NMDA receptor follows research demonstrating the reversal of the antihyperalgesic effect of gabapentin by d ‐serine, an agonist at the NMDA‐glycine binding site . However, receptor binding studies have failed to demonstrate a direct binding site for gabapentin at the NMDA receptor.
The α2δ subunit of the voltage‐dependent calcium channel is a binding site for gabapentin and the S‐isomer of pregabolin (S‐(+)‐3‐isobutylgaba) . Because only gabapentin and the S‐isomer of pregabolin produce antihyperalgesic effects, it is postulated that the antihyperalgesic action for gabapentin is mediated by its binding to this site on the voltage‐dependent calcium channel. Fink et al . showed that, in the rat neocortex, gabapentin inhibits neuronal calcium influx in a concentration‐dependent manner by inhibiting P/Q‐type calcium channels. The decreased calcium influx reduces excitatory amino acid (e.g. glutamate) release leading to decreased AMPA receptor activation, and noradrenaline release in the brain. These findings support the hypothesis that calcium channel inhibition mediates the analgesic effects of gabapentin in chronic neuropathic pain. A decrease in potassium ion‐evoked glutamate release from rat neocortical and hipppocampal slices by gabapentin has been demonstrated .