Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Gabapentin”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources
PubMed1998

A high-performance liquid chromatography micromethod for the simultaneous determination of vigabatrin and gabapentin in serum.

A gradient high-performance liquid chromatography micromethod is described for the simultaneous quantitation of vigabatrin and gabapentin in human serum. Chromatography was performed using a 125- x 3-mm ID Hypersil BDS C-18 column with a 3-microm mini-bore, eluted with a gradient system comprised of phosphate buffer (pH 6.5)-acetonitrile-methanol-water at a flow rate of 0.45 ml/minute. The column eluent was monitored on a fluorescence detector using excitation and emission wavelengths of 340 and 440 nm, respectively. The lower limit of quantitation for vigabatrin and for gabapentin was 5 micromol/l, and the within-batch and between-batch coefficients of variation were <5%. No interference from commonly prescribed antiepileptic drugs (carbamazepine and its metabolite carbamazepine epoxide, oxcarbazepine and its metabolite 10-hydroxycarbazepine, ethosuximide, lamotrigine, phenobarbitone, phenytoin, primidone, and valproic acid) was observed; thus, the method can be used to monitor vigabatrin and gabapentin in patients on polytherapy antiepileptic drug regimens.

Acetates↗
PubMed1999

Skin eruption with gabapentin in a patient with repeated AED-induced Stevens-Johnson's syndrome.

Skin eruptions have been reported with the use of all antiepileptic drugs and there is a significant risk of cross-reactivity between these agents in causing serious eruptions such as Stevens-Johnson's syndrome. Gabepentin is usually considered a safe agent for patients with a previous history of drug allergies and there have been no cases of skin eruption reported to the gabapentin post marketing surveillance. We report a patient who had severe Stevens-Johnson's syndrome induced by phenytoin and later by carbamazepine. Subsequent use of gabapentin also resulted in a skin eruption which was limited to the lower extremities but without systemic or mucosal involvement. This case suggests that patients with a strong history of drug-induced idiosyncratic reactions may experience such reactions to gabapentin as well.

Acetates↗
PubMed2004

Whole-brain glutamate metabolism evaluated by steady-state kinetics using a double-isotope procedure: effects of gabapentin.

Cerebral rates of anaplerosis are known to be significant, yet the rates measured in vivo have been debated. In order to track glutamate metabolism in brain glutamatergic neurons and brain glia, for the first time unrestrained awake rats were continuously infused with a combination of H14CO3- and [1 - 13C]glucose in over 50 infusions ranging from 5 to 60 min. In whole-brain extracts from these animals, the appearance of 14C in brain glutamate and glutamine and appearance of 13C in the C-4 position of glutamate and glutamine were measured as a function of time. The rate of total neuronal glutamate turnover, the anaplerotic rate of synthesis of glutamine and glutamate from H14CO3-, flux through the glutamate/glutamine cycle, and a minimum estimate of whole-brain anaplerosis was obtained. The rate of synthesis of 14C-glutamate from H14CO3- was 1.29 +/- 0.11 nmoles/min/mg protein, whereas the rate of synthesis of 14C-glutamine was 1.48 +/- 0.10 nmoles/min/mg protein compared to total glutamate turnover of 9.39 +/- 0.73 nmoles/min/mg protein. From the turnover rate of glutamine, an upper limit for flux through the glutamate/glutamine cycle was estimated at 4.6 nmoles/min/mg protein. Synthesis of glutamine from H14CO3- was substantial, amounting to 32% of the glutamate/glutamine cycle. These rates were not significantly affected by a single injection of 100 mg/kg of the antiepileptic drug gabapentin. In contrast, acute administration of gabapentin significantly lowered incorporation of H14CO3- into glutamate and glutamine in excised rat retinas, suggesting metabolic effects of gabapentin may require chronic treatment and/or are restricted to brain areas enriched in target enzymes such as the cytosolic branched chain aminotransferase. We conclude that the brain has a high anaplerotic activity and that the combination of two tracers with different precursors affords unique insights into the compartmentation of cerebral metabolism.

Acetates↗
PubMed1995

Gabapentin.

The amino acid antiepileptic drug (AED) gabapentin (GBP) is indicated for adjunctive use in the treatment of partial seizures with or without becoming secondarily generalized in individuals older than 12 years. GBP was about as potent as phenytoin in the maximal electroshock test, but had a different profile of efficacy than standard antiepileptics in a range of animal models. Possible mechanisms of action include biochemical effects enhancing the ratio of gamma-aminobutyric acid (GABA) to glutamate, ion-channel actions (direct or indirect), and/ or enhancement of nonsynaptic GABA release. The anticonvulsant effect appears to depend on concentration of gabapentin in neurons, presumably by the L-system amino acid transporter that has been implicated in absorption from the gut. Data from studies for U.S. Food and Drug Administration (FDA) approval suggested a direct relationship of clinical response to dose and efficacy did not plateau at the doses used. The maximally effective dose, relationship of efficacy to blood level, and maximum tolerable dose are not yet known conclusively. Lack of significant binding to plasma proteins and lack of liver metabolism contribute to the absence of known limiting drug-drug interactions, particularly with other AEDs. Excretion intact in the urine affords dose adjustment on the basis of creatinine clearance. A half-life of approximately 7 h necessitates multiple doses daily for many individuals. The medication is well tolerated, in general. Side effects tend to be mild to moderate in intensity, most frequently affect the central nervous system, and resolve with time in many individuals. GBP has been prescribed for approximately 70,000 individuals worldwide without untoward incidence of severe systemic toxicity to date. Safety data continue to accumulate. GBP has been labeled category C on the basis of effects on rodent fetuses. Experience with use in pregnant women is limited and human teratogenic effects have not been reported. Data from ongoing monotherapy trials will help to clarify the range of clinical utility of gabapentin.

Acetates↗
PubMed1999

Gabapentin as adjunctive therapy for partial seizures.

The safety, tolerability, and efficacy of gabapentin as adjunctive therapy were assessed in epileptic patients who had experienced up to four complex partial seizures per month while receiving phenytoin and/or carbamazepine. This was a multicenter, open-label prospective study, with the treatment period lasting 20 weeks. The gabapentin dosage was titrated to effective tolerated dose up to 2400 mg/day. Quality of life was evaluated with the QOLIE-10 questionnaire. A total of 141 patients were enrolled; 114 patients were evaluated for efficacy analysis. The mean maintenance dose of gabapentin was 1600 mg/day. Seventy-one percent of patients (81 patients) experienced a 50% or greater reduction in seizure frequency and 46% (52 patients) became seizure free. The most frequent adverse effects included drowsiness (16%), dizziness (9%), and asthenia (6%). Sixteen patients (11%) discontinued the study prematurely because of adverse events. A significant improvement was observed in five of the 10 questions of the QOLIE-10.

Acetates↗
PubMed1999

Postherpetic neuralgia: role of gabapentin and other treatment modalities.

Postherpetic neuralgia (PHN) is a chronic and painful condition that may occur after a herpes zoster infection. The frequency of PHN after untreated zoster varies widely. Age is the most important risk factor for development of PHN. The condition occurs in an estimated 50% of patients older than 50 years. The pain of PHN can be severe and debilitating and is frequently associated with allodynia. Although in most patients pain remits within the first year, it may persist for a lifetime. Tricyclic antidepressants (TCAs), topical agents, opioids, and gabapentin, a structural gamma-amino butyric acid (GABA) analogue, are the only agents that have demonstrated efficacy in randomized clinical trials for treatment of both the shooting and the burning form of pain associated with PHN. TCAs are among the most commonly used classes of agents for treating PHN and are effective in a significant proportion of patients. However, various adverse events can limit treatment. These side effects tend to be more acute in the elderly, the population most likely to suffer from PHN. Topical agents have led to mild to moderate improvement in patients with PHN but are usually ineffective as monotherapy for this condition. Until recently, carbamazepine was the only antiepileptic drug evaluated for the treatment of PHN. Over the past few years, however, gabapentin has received increasing attention as a useful treatment for neuropathic pain. Gabapentin lacks significant drug-drug interactions and has a favorable safety profile, which makes it particularly useful for treatment of PHN.

Acetates↗
PubMed1998

A case of myokymia-cramp syndrome successfully treated with gabapentin.

We report a case of "myokymia-cramp syndrome", a rare and benign disease consisting of muscular cramps in the upper and lower limbs associated with generalized myokymias. In our patient, cramps had been present since adolescence and had increased in frequency and duration during the last 3 years, occurring about 8 or 9 times a day. Cramps were mainly nocturnal and also precipitated by walking; a previous treatment with carbamazepine did not improve the symptoms. Gabapentin therapy proved to be very satisfactory in relieving muscular cramps with a relatively low dosage (600 mg/day) and without any remarkable side effects. The possible interpretation of the mechanism involved in gabapentin induced relief of cramps is discussed. Gabapentin should be considered as a safe alternative treatment for muscular cramps.

Acetates↗
PubMed2001

Calcium channel alpha(2)delta subunits-structure and Gabapentin binding.

High-voltage activated calcium channels are modulated by a series of auxiliary proteins, including those of the alpha(2)delta family. Until recently, only a single alpha(2)delta subunit was known, but two further members, alpha(2)delta-2 and -3, have since been identified. In this study, the structure of these two novel subunits has been characterized and binding of the antiepileptic drug gabapentin investigated. Using antibodies directed against the amino terminal portion of the proteins, the gross structure of the subunits could be analyzed by Western blotting. Similar to alpha(2)delta-1, both alpha(2)delta-2 and -3 subunits consist of two proteins-a larger alpha(2) and a smaller delta that can be separated by reduction. The subunits are also highly N-glycosylated with approximately 30 kDa of their mass consisting of oligosaccharides. alpha(2)delta-1 was detected in all mouse tissues studied, whereas alpha(2)delta-2 was found at high levels in brain and heart. The alpha(2)delta-3 subunit was observed only in brain. alpha(2)delta-1 and alpha(2)delta-2, but not alpha(2)delta-3, were found to bind gabapentin. The K(d) value of gabapentin binding to alpha(2)delta-2 was 153 nM compared with the higher affinity binding to alpha(2)delta-1 (K(d) = 59 nM).

Acetates↗
PubMed2002

Dissociation of charge movement from calcium release and calcium current in skeletal myotubes by gabapentin.

The skeletal muscle L-type calcium channel or dihydropyridine receptor (DHPR) plays an integral role in excitation-contraction (E-C) coupling. Its activation initiates three sequential events: charge movement (Q(r)), calcium release, and calcium current (I(Ca,L)). This relationship suggests that changes in Q(r) might affect release and I(Ca,L). Here we studied the effect of gabapentin (GBP) on the three events generated by DHPRs in skeletal myotubes in culture. GBP specifically binds to the alpha(2)/delta(1) subunit of the brain and skeletal muscle DHPR. Myotubes were stimulated with a protocol that included a depolarizing prepulse to inactivate voltage-dependent proteins other than DHPRs. Gabapentin (50 microM) significantly increased Q(r) while decreasing the rate of rise of calcium transients. Gabapentin also reduced the maximum amplitude of the I(Ca,L) (as we previously reported) without modifying the kinetics of activation. Exposure of GBP-treated myotubes to 10 microM nifedipine prevented the increase of Q(r) promoted by this drug, indicating that the extra charge recorded originated from DHPRs. Our data suggest that GBP dissociates the functions of the DHPR from the initial voltage-sensing step and implicates a role for the alpha(2)/delta(1) subunit in E-C coupling.

Acetates↗
PubMed1999

Gabapentin as treatment for hemifacial spasm.

Hemifacial spasm, a life-long condition characterized by involuntary unilateral contractions of the facial muscles, is a disabling disorder often resulting in patient irritation and social embarassment. Its probable etiology is neurovascular compression of the facial nerve at its root exit zone. The current medical treatment consists of either baclofen or anticonvulsant drugs, with limitation due to side effects or low efficacy. In recent years botulinum toxin injection and microvascular decompression of the facial nerve have been shown to be highly successful. However, both procedures share some complications and require special techniques. We present 5 patients affected by hemifacial spasm who responded well to the novel anticonvulsant drug gabapentin. Gabapentin was administered at a dose ranging from 900 to 1,600 mg daily, with rapid and clear improvement of spasms and absence of any remarkable adverse effects. Our findings suggest that gabapentin may be an effective treatment for patients with hemifacial spasm with a very good ratio of therapeutic effects to side effects when compared with other drugs currently used.

Acetates↗
PubMed2005

Gabapentin for the symptomatic treatment of chronic neuropathic pain in patients with late-stage lyme borreliosis: a pilot study.

BACKGROUND: Chronic neuropathic pain occurs in 10-15% of patients with neuroborreliosis and is difficult to treat. OBJECTIVE: We evaluated the effect of gabapentin monotherapy on residual pain in patients with neuroborreliosis after intravenous ceftriaxone treatment. METHODS: Ten patients with neuroborreliosis and a long-lasting history of neurologic symptoms were treated with gabapentin, starting with 300 mg/day. Doses were raised over a period of 4-12 weeks to the individually effective and tolerated maximum dose (500-1,200 mg). Treatment was maintained until pain disappeared and then gradually reduced in dose over weeks. If symptoms recurred, the doses were raised again. Therapy was maintained over an average of 1-2 years. RESULTS: Pain quality and pain quantity were evaluated using the McGill pain questionnaire and a visual analogue scale. There was an improvement of 'crawling' and 'burning' pain sensations, neck and radiating lumbar pain in 9/10 (90%) patients as well as a positive effect on mood, general feeling of health and quality of sleep in 5/10 (50%) patients. The average dose leading to a clear-cut pain reduction was 700 mg. CONCLUSIONS: In an open pilot study (10 patients), gabapentin monotherapy which has to our knowledge not been published as treatment of chronic neuropathic pain in patients with late Lyme borreliosis is efficacious in treating pain associated with neuroborreliosis and can thus improve quality of life in these patients.

Administration, Oral↗
PubMed2000

Treatment of dementia-associated agitation with gabapentin.

The authors describe the use of gabapentin in the treatment of 4 outpatients with dementia-associated agitation. On the basis of clinical case reports and the Overt Agitation Severity Scale, all 4 patients had reduced agitation with gabapentin. Three of 4 patients were successfully titrated to a full dose of 2,400mg/day. These findings suggest a possible role for gabapentin in the behavioral management of patients with dementia.

Acetates↗
PubMed2003

Role of gabapentin in spinal muscular atrophy: results of a multicenter, randomized Italian study.

Recent studies suggest that gabapentin has a neuroprotective effect in experimental models of motoneuron disease. We carried out a multicenter, randomized, controlled trial of gabapentin versus no treatment in 120 patients with type II or III spinal muscular atrophy for 12 months. We assessed maximum voluntary isometric contraction with a handheld myometer and calculated an arm megascore (summing elbow flexion, hand grip, and three-point pinch scores), and a leg megascore (summing knee flexion, knee extension, and foot extension scores). Forced vital capacity and timed tasks were also evaluated. Arm megascore improved by at least 30% in 24.6% of treated and 16.9% of untreated patients (relative risk = 1.45; 95% confidence interval = 0.71-2.97). The leg megascore improved by at least 30% in 37.7% of treated and 20.3% of untreated patients (relative risk = 1.85; 95% confidence interval = 1.02-3.37). We conclude that gabapentin produced a significant improvement in leg megascore at 6 months, which was more evident at 12 months, with a trend for improvement in arm megascore at 12 months. The treatment had no effect on forced vital capacity or timed functional tests.

Acetates↗
PubMed2003

Gabapentin for the treatment of tremor.

OBJECTIVE: To review the use of the antiepileptic drug gabapentin for the treatment of various types of tremor. DATA SOURCES: A search of biomedical literature was completed through MEDLINE and EMBASE (1993-May 2002) to identify all clinical trials pertaining to the use of gabapentin for the treatment of tremor in humans. DATA SYNTHESIS: Outcome data from the few published studies have varied widely. Patient groups have been small, and conclusions have been based largely on subjective patient and investigator ratings. CONCLUSIONS: A trial of gabapentin is warranted in patients who fail therapy with traditional agents. Improvement should be measured by a patient's perceived functional ability.

Acetates↗
PubMed1997

Open label gabapentin treatment for pain in multiple sclerosis.

Pain is a frequent and distressing complaint in patients with multiple sclerosis (MS) and may present a difficult therapeutic problem. Conventional therapy is moderately effective and includes, among others, a variety of anticonvulsant medications. Gabapentin (Neurontin) is a new generation antiepileptic drug which appears to be advantageous in treatment of intractable pain of reflex sympathetic dystrophy. This study investigates the benefits of open-label treatment with gabapentin for pain control in 25 patients with MS. Excellent to moderate pain relief was obtained in a substantial number of patients. Throbbing pains and needles, and cramping pains responded best, and dull aching pains responded least to the medication. There was no significant change in distribution and type of pain as a result of this treatment. Mild to moderate side effects were observed. Cautious escalation of the dose of gabapentin is advisable in MS patients. Further clinical trials with larger patient groups are recommended.

Acetates↗
PubMed2004

Gabapentin in the treatment of neuropathic pain.

This paper reviews the pharmacology and clinical effectiveness of gabapentin in the treatment of neuropathic pain. Gabapentin has antihyperalgesic and antiallodynic properties but does not have significant actions as an anti-nociceptive agent. Its mechanisms of action appear to be a complex synergy between increased GABA synthesis, non-NMDA receptor antagonism and binding to the alpha2delta subunit of voltage dependent calcium channels. The latter action inhibits the release of excitatory neurotransmitters. Clinically, several large randomized controlled trials have demonstrated its effectiveness in the treatment of a variety of neuropathic pain syndromes. Patients with neuropathic pain can expect a mean reduction in pain score of 2.05 points on an 11 point numerical rating scale compared with a reduction of 0.94 points if they had taken the placebo. Around 30% of patients can expect to achieve more than 50% pain relief and a similar number will also experience minor adverse events; the most common of which are somnolence and dizziness. In patients with neuropathic pain due to cancer, higher response rates might be observed with gabapentin when administered with opioids because of a synergistic interaction.

Acetates↗
PubMed2005

Unbiased membrane permeability parameters for gabapentin using boundary layer approach.

The present study was performed to determine the relative contribution of both passive and nonpassive transport processes in jejunal absorption of gabapentin. The oral absorption of gabapentin was studied using in situ single pass intestinal perfusion technique in fasted rats. Unbiased intrinsic membrane absorption parameters such as maximal flux, Michaelis constant, carrier permeability, and membrane permeability were calculated using a modified boundary layer model. Gabapentin intestinal perfusion results indicate that its jejunal absorption in rats occurs via a nonpassive process, with no significant passive absorption component, as demonstrated by saturable absorption kinetics and its concentration-dependent permeability. A good correlation (r2 = 0.88) between observed human absorption fraction and calculated (from in situ rat intestine) human absorption fraction was obtained.

Algorithms↗
PubMed2005

A single dose of gabapentin reduces acute pain and allodynia in patients with herpes zoster.

This randomized, double-blind, placebo-controlled crossover study measured the effect of a single dose of oral gabapentin (900 mg) on pain and allodynia associated with herpes zoster. Pain severity decreased by 66% with gabapentin compared to 33% with placebo. Reductions in allodynia area and severity, and overall pain relief, were also greater with gabapentin.

Acute Disease↗