topiramate and Status-Epilepticus

There is considerable clinical evidence that topiramate (TPM) has a high potential in the treatment of refractory and super-refractory status epilepticus (RSE, SRSE). Because TPM is only approved for oral administration, it is applied as suspension via a nasogastric tube for SE treatment. However, this route of administration is impractical in an emergency setting and leads to variable absorption with unpredictable plasma levels and time to peak concentration. Thus, the development of an intravenous (i.v.) solution for TPM is highly desirable. Here we present data on two parenteral formulations of TPM that are currently being developed. One of these solutions is using sulfobutylether-β-cyclodextrin (SBE-β-CD; Captisol®) as an excipient. A 1% solution of TPM in 10% Captisol® has been reported to be well tolerated in safety studies in healthy volunteers and patients with epilepsy or migraine, but efficacy data are not available. The other solution uses the FDA- and EMA-approved excipient amino sugar meglumine. Meglumine is much more effective to dissolve TPM in water than Captisol®. A 1% solution of TPM can be achieved with 0.5-1% of meglumine. While the use of Captisol®-containing solutions is restricted in children and patients with renal impairment, such restrictions do not apply to meglumine. Recently, first-in-human data were reported for a meglumine-based solution of TPM, indicating safety and efficacy when used as a replacement for oral administration in a woman with epilepsy. Based on the multiple mechanisms of action of TPM that directly target the molecular neuronal alterations that are thought to underlie the loss of efficacy of benzodiazepines and other anti-seizure medications during prolonged SE and its rapid brain penetration after i.v. administration, we suggest that parenteral (i.v.) TPM is ideally suited for the treatment of RSE and SRSE. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Topics: Anticonvulsants; Child; Excipients; Female; Fructose; Humans; Status Epilepticus; Topiramate

Status epilepticus is defined as the situation resulting from the failure of the mechanisms responsible for terminating an epileptic seizure. In 2015, an operational concept was adopted internationally in which two times are identified: a first time, at which treatment must begin (five minutes for convulsive status, 10-15 minutes for focal and non-convulsive status); and a second time, after which there is considered to be a high risk of subsequent sequelae (30 minutes in the case of the convulsive). It occurs in 3-42/100,000 children per year, who are refractory or super-refractory in 10-40% of cases.. This article will review the different therapeutic options for status, from early treatment at home to the different first-line (benzodiazepines), second-line (phenobarbital, valproic acid, phenytoin, levetiracetam and lacosamide) or third-line treatments, which include both pharmacological (anaesthetics, propofol, ketamine, lidocaine, topiramate, brivaracetam or perampanel) and non-pharmacological (ketogenic diet, immunomodulatory treatments or epilepsy surgery) therapies.. Early identification and treatment of a prolonged crisis are essential to prevent progression to status. Although with fewer sequelae than in adults, status epilepticus in children represents a cause of mortality of up to 3-5%, while 25% of them will develop subsequent epilepsy, as well as a considerable percentage of neurological sequelae.. Estado epiléptico pediátrico.. Introducción. El estado epiléptico se define como la situación resultante del fallo de los mecanismos responsables de finalizar una crisis epiléptica. En 2015, se adoptó internacionalmente un concepto operativo en el que se identifican dos tiempos: un primer momento, en el que hay que comenzar un tratamiento (cinco minutos para los estados convulsivos, 10-15 minutos para los estados focales y no convulsivos); y un segundo tiempo, a partir del cual se considera que hay un riesgo elevado de secuelas posteriores (30 minutos en los convulsivos). Ocurre en 3-42/100.000 niños al año, y son refractarios o superrefractarios en el 10-40% de las ocasiones. Desarrollo. En este artículo se revisarán las diferentes opciones terapéuticas del estado, desde el tratamiento precoz domiciliario hasta los diferentes tratamientos de primera línea (benzodiacepinas), segunda línea (fenobarbital, ácido valproico, fenitoína, levetiracetam y lacosamida) o tercera línea, que incluyen tanto terapias farmacológicas (anestésicos, propofol, cetamina, lidocaína, topiramato, brivaracetam o perampanel) como no farmacológicas (dieta cetógena, tratamientos inmunomoduladores o cirugía de epilepsia). Conclusiones. Son fundamentales la identificación y el tratamiento precoz de una crisis prolongada para evitar la evolución a estado. Aunque con menores secuelas que en los adultos, el estado epiléptico en niños representa una causa de mortalidad hasta del 3-5%, al mismo tiempo que un 25% de ellos desarrollará una epilepsia posterior, así como un porcentaje considerable de secuelas neurológicas.

Topics: Adult; Anesthetics; Anticonvulsants; Benzodiazepines; Child; Epilepsy; Humans; Ketamine; Lacosamide; Levetiracetam; Lidocaine; Phenobarbital; Phenytoin; Propofol; Seizures; Status Epilepticus; Topiramate; Valproic Acid

To identify current evidence on the use of topiramate for refractory status epilepticus.. We reviewed the literature to investigate the efficacy of topiramate in the treatment of refractory status epilepticus. The search terms used were "status epilepticus", "refractory", "treatment" and "topiramate". No restrictions were used.. The search yielded 487 articles that reported using topiramate as a treatment for refractory status epilepticus and its outcomes. Case reports, review articles, and animal experiments were excluded. After excluding duplicates and applying inclusion and exclusion criteria, nine studies were included for analyses. Descriptive and qualitative analyses were performed, and the results were as follows: response rates (defined as termination in-hospital until 72 hours after the administration of topiramate) varied from 27% to 100%. The mortality rate varied from 5.9% to 68%. Positive functional long-term outcomes, defined as discharge, back to baseline or rehabilitation, were documented by seven studies, and the rates ranged between 4% and 55%. Most studies reported no or mild adverse effects.. Topiramate was effective in terminating refractory status epilepticus, presented relatively low mortality and was well tolerated. Therefore, topiramate could be a good option as a third-line therapy for refractory status epilepticus, but further studies are necessary.. Identificar evidências atuais sobre topiramato para o estado de mal epiléptico refratário.. Foi revisada a literatura para investigar a eficácia do topiramato no tratamento de estado de mal epiléptico refratário. Os termos de busca utilizados foram: “status epilepticus”, “refractory”, “treatment” e “topiramate”. Não se empregaram restrições.. A busca identificou 487 artigos que descreviam o uso de topiramato para tratamento de estado de mal epiléptico refratário e seus resultados. Relatos de caso, revisões e experimentos em animais foram excluídos. Após exclusão de duplicatas e aplicação dos critérios de inclusão e exclusão, restaram nove estudos. Realizaram-se análises descritivas e qualitativas, com os seguintes resultados: as taxas de resposta, definidas como término de crises até 72 horas após administração de topiramato, variaram entre 27% e 100%. A mortalidade variou de 5,9% a 68%. Desfechos funcionais positivos, definidos como alta hospitalar, volta à funcionalidade basal ou reabilitação, foram documentados por sete estudos, e as taxas variaram entre 4% e 55%. A maioria dos estudos reportou apenas efeitos colaterais leves ou ausentes.. Topiramato foi efetivo em abortar estado de mal epiléptico refratário, apresentando baixa mortalidade e boa tolerabilidade. Portanto, topiramato poderia ser uma boa opção como terceira linha para estado de mal epiléptico refratário, porém mais estudos são necessários.

Topics: Animals; Anticonvulsants; Humans; Status Epilepticus; Topiramate

Generalized convulsive status epilepticus (GCSE) is a medical emergency associated with high morbidity and mortality that requires prompt medical intervention. Topiramate (TPM) is an antiepileptic drug effective against a broad spectrum of seizure types, and has been proposed as a possible therapeutic option for super-refractory status epilepticus (SRSE), the most severe form of GCSE.. This review aimed to evaluate the role of TPM in GCSE, including SRSE.. MEDLINE, CENTRAL, ClinicalTrials.gov, LILACS, Google Scholar, and Opengrey.eu were systematically searched. We compared: (1) patients who did and who did not receive TPM as their last drug; (2) patients receiving TPM as the last drug and achieving SE control and patients receiving TPM as the last drug but without termination of SE.. The literature search yielded 1164 results, with individual data available for 35 patients (six with SRSE) from four studies. SE was controlled in 68.6% of patients receiving TPM either as the last drug (20) or not (15), and in 14 of the 20 patients receiving TPM as the last drug (70%). Only six patients received TPM for SRSE; in five of them, TPM was administered as the last drug with resolution of SE in four. When comparing patients who did and did not receive TPM as the last drug, no statistically significant difference was found for any of the variables considered; similarly, no difference was found comparing patients receiving TPM as the last drug and achieving SE control with those receiving TPM as the last drug but without termination of SE.. The lack of a statistically significant difference is likely to be due to the small sample size. In only a few patients was TPM used for SRSE. There is an unmet need for high-quality studies to evaluate the role of TPM in GCSE.

Topics: Adult; Anticonvulsants; Fructose; Humans; Status Epilepticus; Topiramate

The pharmacokinetics and pharmacodynamics of major antiepileptic agents are presented. The onset of action and the factors leading to extraction across the blood brain barrier are described as well as the mechanism and extent of metabolism, and the main interactions with other drugs. For each class, the dosing scheme and practical issues related to administration are described, based on evidence when available in the literature.

Topics: Anticonvulsants; Barbiturates; Benzodiazepines; Fructose; Humans; Hypnotics and Sedatives; Levetiracetam; Phenytoin; Piracetam; Propofol; Status Epilepticus; Topiramate; Valproic Acid

Topics: Acetamides; Animals; Anticonvulsants; Carbamates; Disease Models, Animal; Fructose; Humans; Lacosamide; Pyrroles; Pyrrolidinones; Rats; Receptors, AMPA; Status Epilepticus; Tetrahydroisoquinolines; Topiramate; Treatment Outcome

Topics: Anticonvulsants; Drug Approval; Fructose; Humans; Infusions, Intravenous; Injections, Intravenous; Levetiracetam; Piracetam; Status Epilepticus; Topiramate; United States; Valproic Acid

Refractory status epilepticus (RSE) is an important and serious clinical problem that typically requires prolonged and high-level intensive care, and is often associated with poor outcome. This review addresses some of the current issues concerning the management of RSE, including recent definitions used for clinical studies, epidemiology, clinical course, and outcome. Current approaches to treatment, including the now relatively standard use of intravenous anesthetic agents, as well as emerging therapies utilizing drugs such as valproate and topiramate, are discussed as well.

Topics: Anesthetics; Anticonvulsants; Clinical Protocols; Decision Trees; Drug Administration Schedule; Drug Resistance; Fructose; Health Care Surveys; Humans; Practice Patterns, Physicians'; Status Epilepticus; Terminology as Topic; Topiramate; Treatment Outcome; Valproic Acid

In cases of refractory status epilepticus (RSE) unresponsive to sequential trials of multiple agents, a suspension of topiramate administered via nasogastric tube was effective in aborting RSE, including one patient in a prolonged pentobarbital coma. Effective dosages ranged from 300 to 1,600 mg/d. Except for lethargy, no adverse events were reported.

Topics: Adult; Aged; Anticonvulsants; Databases, Factual; Drug Resistance; Female; Fructose; Humans; Intubation, Gastrointestinal; Male; Middle Aged; Retrospective Studies; Status Epilepticus; Topiramate; Treatment Outcome

For an antiseizure medication (ASM) to be effective in status epilepticus (SE), the drug should be administered intravenously (i.v.) to provide quick access to the brain. However, poor aqueous solubility is a major problem in the development of parenteral drug solutions. Given its multiple mechanisms of action, topiramate (TPM) is a promising candidate for the treatment of established or refractory SE, as supported by clinical studies using nasogastric tube TPM administration. However, TPM is not clinically available as a solution for i.v. administration, which hampers its use in the treatment of SE. Here, we describe a novel easy-to-use and easy-to-prepare i.v. TPM formulation using the U.S. Food and Drug Administration (FDA)-approved excipient meglumine.. During formulation development, we compared the solubility of TPM in bi-distilled water with vs without a range of meglumine concentrations. Furthermore, the solubility of combinations of TPM and levetiracetam and TPM, levetiracetam, and atorvastatin in aqueous meglumine concentrations was determined. Subsequently, the pharmacokinetics and tolerability of meglumine-based solutions of TPM and TPM combinations were evaluated in rats, including animals following fluid percussion injury or pilocarpine-induced SE.. The amino sugar meglumine markedly enhances the aqueous solubility of TPM. A comparison with data on dissolving TPM using sulfobutylether-β-cyclodextrin (Captisol) demonstrates that meglumine is much more effective for dissolving TPM. Furthermore, meglumine can be used to prepare drug cocktails where TPM is co-administered with another ASM for SE treatment. The tolerability studies of the meglumine-based TPM solution and meglumine-based TPM combinations in normal rats and the rat fluid percussion injury and pilocarpine-induced SE models demonstrate excellent tolerability of the novel drug solutions. Preclinical studies on antiseizure efficacy in the SE model are underway.. In conclusion, the novel meglumine-based solution of TPM presented here may be well suited for clinical development.

Topics: Animals; Anticonvulsants; Fructose; Levetiracetam; Pilocarpine; Rats; Status Epilepticus; Topiramate

Topics: Anticonvulsants; Humans; Status Epilepticus; Topiramate

Status epilepticus in poststroke epilepsy is a challenging condition because of multiple vascular comorbidities and the advanced age of patients. Data on third-generation antiseizure medication (ASM) in this condition are limited. The aim of this study was to evaluate the efficacy of third-generation ASMs in the second- or third-line therapy of benzodiazepine-refractory status epilepticus in poststroke epilepsy following acute ischemic stroke.. Data on the effectiveness of third-generation ASMs in patients with status epilepticus in poststroke epilepsy were gathered from two German Stroke Registries and the Mainz Epilepsy Registry. We included only cases with epilepsy remote to the ischemic event. No patients with acute symptomatic seizures were included. The following third-generation ASMs were included: brivaracetam, lacosamide, eslicarbazepine, perampanel, topiramate, and zonisamide. The assessment of effectiveness was based on seizure freedom within 48 h since the start of therapy with the respective ASM. Seizure freedom was evaluated both clinically (clinical evaluation at least three times per day) and by daily electroencephalogram records.. Of the 138 patients aged 70.8 ± 8.1 years with benzodiazepine-refractory status epilepticus in ischemic poststroke epilepsy, 33 (23.9%) were treated with lacosamide, 24 (17.4%) with brivaracetam, 23 (16.7%) with eslicarbazepine, 21 (15.2%) with perampanel, 20 (14.5%) with topiramate, and 17 (12.3%) with zonisamide. Seizure freedom within 48 h was achieved in 66.7% of patients with lacosamide, 65.2% with eslicarbazepine, 38.1% with perampanel, 37.5% with brivaracetam, 35.0% with topiramate, and 35.3% with zonisamide (p < 0.05 for comparison of lacosamide or eslicarbazepine to other ASMs).. Based on these data, lacosamide and eslicarbazepine might be more favorable in the treatment of refractory status epilepticus in poststroke epilepsy, when administered as second- or third-line ASMs before anesthesia. Because of the fact that these ASMs share the same mechanism of action (slow inactivation of sodium channels), our findings could motivate further research on the role that this pharmaceutical mechanism of action has in the treatment of poststroke epilepsy.. This study was registered at ClinicalTrials.gov (NCT05267405).

Topics: Aged; Anticonvulsants; Benzodiazepines; Epilepsy; Humans; Ischemic Stroke; Lacosamide; Middle Aged; Retrospective Studies; Seizures; Status Epilepticus; Topiramate; Zonisamide

Epilepsy is a widespread neurological disorder frequently associated with a lot of comorbidities. The present study aimed to evaluate the effects of the antiseizure medication topiramate (TPM) on spontaneous motor seizures, the pathogenesis of comorbid mood and cognitive impairments, hippocampal neuronal loss, and oxidative stress and inflammation in a rat model of temporal lobe epilepsy (TLE). Vehicle/TPM treatment (80 mg/kg, p.o.) was administered 3 h after the pilocarpine (pilo)-induced status epilepticus (SE) and continued for up to 12 weeks in Wistar rats. The chronic TPM treatment caused side effects in naïve rats, including memory disturbance, anxiety, and depressive-like responses. However, the anticonvulsant effect of this drug, administered during epileptogenesis, was accompanied by beneficial activity against comorbid behavioral impairments. The drug treatment suppressed the SE-induced neuronal damage in limbic structures, including the dorsal (CA1 and CA2 subfield), the ventral (CA1, CA2 and CA3) hippocampus, the basolateral amygdala, and the piriform cortex, while was ineffective against the surge in the oxidative stress and inflammation. Our results suggest that neuroprotection is an essential mechanism of TPM against spontaneous generalized seizures and concomitant emotional and cognitive impairments.

Topics: Animals; Anticonvulsants; Disease Models, Animal; Epilepsy, Temporal Lobe; Hippocampus; Inflammation; Neuroprotection; Pilocarpine; Rats; Rats, Wistar; Seizures; Status Epilepticus; Topiramate

Status epilepticus (SE) is a neurological disorder characterized by a prolonged epileptic activity followed by subsequent epileptogenic processes. The aim of the present study was to evaluate the early effects of topiramate (TPM) and lacosamide (LCM) treatment on oxidative stress and inflammatory damage in a model of pilocarpine-induced SE.. Male Wistar rats were randomly divided into six groups and the two antiepileptic drugs (AEDs), TPM (40 and 80 mg/kg, i.p.) and LCM (10 and 30 mg/kg, i.p.), were injected three times repeatedly after pilocarpine administration. Rats were sacrificed 24 h post-SE and several parameters of oxidative stress and inflammatory response have been explored in the hippocampus.. The two drugs TPM and LCM, in both doses used, succeeded in attenuating the number of motor seizures compared to the SE-veh group 30 min after administration. Pilocarpine-induced SE decreased the superoxide dismutase (SOD) activity and reduced glutathione (GSH) levels while increasing the catalase (CAT) activity, malondialdehyde (MDA), and IL-1β levels compared to the control group. Groups with SE did not affect the TNF-α levels. The treatment with a higher dose of 30 mg/kg LCM restored to control level the SOD activity in the SE group. The two AEDs, in both doses applied, also normalized the CAT activity and MDA levels to control values. In conclusion, we suggest that the antioxidant effect of TPM and LCM might contribute to their anticonvulsant effect against pilocarpine-induced SE, whereas their weak anti-inflammatory effect in the hippocampus is a consequence of reduced SE severity.

Topics: Animals; Anticonvulsants; Biomarkers; Hippocampus; Inflammation; Interleukin-1beta; Lacosamide; Male; Motor Activity; Oxidative Stress; Pilocarpine; Rats, Wistar; Reactive Oxygen Species; Seizures; Status Epilepticus; Topiramate; Tumor Necrosis Factor-alpha

Epilepsy and antiepileptic drugs can affect negatively the cognitive abilities of patients.. The present study aimed to evaluate the effect of topiramate (TPM) and lacosamide (LCM) on the emotional and cognitive re-sponses in naive animals and in animals with pilocarpine-induced status epilepticus.. Male Wistar rats were randomly divided into 6 groups and status epilepticus was evoked in half of them by a single i.p. administration of pilocarpine (Pilo) (320 mg/kg): Pilo-veh, Pilo-TPM (80 mg/kg) and Pilo-LCM (30 mg/kg). Matched naive rats were treated with the same doses as follows: C-veh, C-TPM, and C-LCM. In a step-down passive avoidance test, the learning session was held for one day, the early retention test was conducted on day 2, and the long-term memory test - on day 7. Motor activity and anxiety were evaluated in an open field test.. The Pilo-TPM and Pilo-LCM groups increased the time spent on the platform compared to Pilo-veh animals while the C-LCM animals decreased the time compared to C-veh animals during short- and long-term memory retention tests. TPM and LCM exerted an anxiolytic effect in naive rats. The two antiepileptic drugs were unable to alleviate the hyperactivity, but they alleviated the impulsivity associated with decreased anxiety level in epileptic rats.. Our findings suggest that LCM and TPM have a beneficial effect on cognition both in naive and epileptic rats. While the two antiepileptic drugs can produce an anxiolytic effect in naive rats, they alleviate the impulsivity after pilocarpine treatment.

Topics: Animals; Anticonvulsants; Cognition; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Emotional Regulation; Follow-Up Studies; Lacosamide; Male; Pilocarpine; Rats; Rats, Wistar; Status Epilepticus; Time Factors; Topiramate

The aim of this study was to assess factors associated with the use of topiramate (TPM) in refractory status epilepticus (RSE).. We retrospectively reviewed RSE episodes over a 12-year period. Episodes treated with and without TPM were compared in terms of demographics, RSE characteristics, clinical course, and outcome in univariate and multivariate analyses. Subgroups defined by type of RSE were studied separately. Functional outcome was assessed with the modified Rankin Scale.. Among 71 episodes, 17 (23.9%) were treated with TPM and seizure control was achieved in all of these. The results of unadjusted comparisons suggested a use of TPM in younger and healthier patients who received more perseverant treatment indicated by a higher number of antiepileptic drugs applied. In multivariate analysis adjusting for RSE duration, however, these associations lost significance. Furthermore, TPM was not a predictor of successful RSE termination in neither the overall cohort, nor in the subgroup of complex-partial RSE.. After multivariate adjustment, no significant differences were observed between episodes treated with and without TPM in baseline characteristics, treatment, and outcome. Regarding the latter, this study does therefore not yield evidence for a particular efficacy of TPM in RSE.

Topics: Adult; Aged; Aged, 80 and over; Anticonvulsants; Drug Resistant Epilepsy; Female; Fructose; Humans; Male; Middle Aged; Outcome Assessment, Health Care; Retrospective Studies; Status Epilepticus; Topiramate

To explore the feasibility, safety and efficacy of enterally administered topiramate (TPM) as an adjunctive treatment for adult patients with refractory generalized convulsive status epilepticus (RGCSE).. This prospective open-label non-randomized clinical trial was performed at Namazee hospital, Shiraz University of Medical Sciences, Shiraz, Iran from January 2013 through February 2014. Patients 18 years of age and older with RGCSE were enrolled. Topiramate was used, in case of failure of at least two standard anti-epileptic drugs in patients in whom the standard third or fourth line therapies were not available. Topiramate tablets were crushed and administered through the nasogastric tube; 400mg stat and then 200mg Bid. Status epilepticus response to TPM was categorized as successful (termination of SE within 24h following TPM introduction, without modification of concomitant AEDs), possible (SE termination associated with the introduction of TPM, concomitantly with other medications) or unsuccessful.. Twenty patients were studied. Topiramate was successful in terminating SE in five (25%) patients; possibly successful in 11 (55%); and not successful in four (20%). No clinically significant adverse effects related to TPM administration were observed. Eleven (55%) patients returned to their baseline clinical condition at the time of discharge from the hospital, but two (10%) patients did not.. Treatment with enterally administered topiramate could potentially be efficacious in some patients and appeared to be tolerated well in patients with RGCSE. Low cost and feasibility makes TPM a potentially useful agent in treating patients with RGCSE, especially in resource limited settings.

Topics: Administration, Rectal; Adolescent; Adult; Aged; Aged, 80 and over; Anticonvulsants; Electroencephalography; Female; Fructose; Humans; Male; Middle Aged; Prospective Studies; Retrospective Studies; Status Epilepticus; Topiramate; Treatment Outcome; Young Adult

To investigate the relationships between demographic data, seizure-related factors, anti-epileptic drugs (AEDs) taking, and depressive symptoms in patients with epilepsy (PWE), determining the major clinical risk factors of depression.. Patients with epilepsy who visited our epilepsy clinic from 2010 to 2012 were included. The clinical data were collected, and Hamilton Depression Rating Scale (HAMD), National Hospital Seizure Severity Scale (NHS3) and Pittsburgh Sleep Quality Index (PSQI) were evaluated.. A total of 116 PWE were recruited. They were divided into three groups. Age, duration of epilepsy, percentages of patients with partial seizures, history of status epilepticus (SE), using topiramate (TPM) or clonazepam (CZP), and using greater than or equal to 2 types of AEDs were all significantly higher in patients with moderate depressive symptoms than patients without depression. HAMD scores were positively correlated with age, duration of epilepsy, and the number of AEDs taking, respectively. PSQI scores were positively correlated with HAMD scores in patients with depressive symptoms. Age greater than 35 years, females, having partial seizures, history of SE, and using TPM were independent predictors of depressive symptoms in PWE by regression analysis.. Age greater than 35 years, females, having partial seizures, history of SE, and using TPM might become risk factors for depressive symptoms in PWE.

Topics: Adolescent; Adult; Age Factors; Anticonvulsants; Depression; Epilepsies, Partial; Epilepsy; Female; Fructose; Humans; Male; Middle Aged; Prospective Studies; Risk Factors; Sex Factors; Status Epilepticus; Time Factors; Topiramate; Young Adult

Oral anti-epileptic drugs (AED) represent possible add-on options in refractory status epilepticus (SE). We report our experience in using topiramate (TPM) to treat SE unresponsive to sequential trials of multiple agents.. Over 57 months, we identified 11 SE patients treated with TPM in our hospital, all of them suffered from SE refractory to at least two treatments, and six had generalized SE. Nine patients were managed in the ICU and required intubation.. We found a definite electro-clinical response in 2/11 patients, already evident after 12-96 h after TPM introduction, and a possible response in 2/11 patients (concomitantly with other AEDs); 7/11 did not respond. Partial-complex SE appeared to better respond than generalized-convulsive SE. One patient developed a severe nephrolithiasis.. As compared to previous small series describing only patients responding to TPM, this unselected observation underscores the difficulty of treating refractory SE, regardless of the agent.

Topics: Administration, Oral; Adolescent; Adult; Aged; Aged, 80 and over; Anticonvulsants; Drug Therapy, Combination; Female; Fructose; Humans; Male; Middle Aged; Prospective Studies; Status Epilepticus; Topiramate; Treatment Outcome; Young Adult

Refractory status epilepticus (RSE) occurs in patients with SE when they fail to respond to traditional medical therapy. Because there are very few case reports of topiramate (TPM) treatment of RSE in adult patients, we examined our experience with TPM with regard to its safety and efficacy in seizure termination in RSE in an adult patient population. We report a retrospective review of 35 adult patients with RSE who were treated with TPM in addition to other antiepileptic drugs (AEDs) between 2003 and 2010. After failure of initial treatments of benzodiazepines and weight-based intravenous loading doses of standard AEDs, TPM tablets were crushed and administered via nasogastric tube. Data were collected on age, gender, history of epilepsy, etiology of RSE, daily dose of TPM, co-therapeutic agents, treatment response, and disposition. Following initiation of TPM use and discontinuation of continuous intravenous anesthetics with no additional AEDs administered, cumulative cessation of RSE in patients was 4/35 (11%) at one day, 10/35 (29%) at two days, and 14/35 (40%) at three days. However, when including all patients and comparing the two patient groups in which RSE was or was not terminated within three days of initiating TPM as the last or not last AED given, there was no significant difference. Time to TPM response was not associated with the type of seizures, etiology of SE, or whether there was a history of epilepsy. There were no documented side effects or complications of therapy with TPM. This study provides support for the use of TPM as an adjunctive agent in the treatment of RSE.

Topics: Adult; Aged; Aged, 80 and over; Anticonvulsants; Female; Fructose; Humans; Male; Middle Aged; Retrospective Studies; Seizures; Status Epilepticus; Time Factors; Topiramate; Young Adult

Psychogenic nonepileptic seizures are clinical events that mimic epileptic seizures but are not associated with electroencephalographic discharges. These seizures are seldom reported in children in the literature and could be misinterpreted as generalized tonicoclonic seizures. We report the case of a child, already treated for epilepsy, who presented at 8 years of age with several psychogenic seizures leading to pseudostatus epilepticus. After several hospitalizations, the diagnosis of pseudostatus was established on the basis of clinical semiology, lack of EEG abnormalities during the seizures, and a positive provocation maneuver, which elicited and blocked the manifestations. The clinical spectrum of psychogenic seizures is wide and it is particularly difficult to differentiate psychogenic seizures from epileptic seizures, especially when occurring in children, some of whom are already treated for epilepsy. Well-described clinical features can suggest the diagnosis of psychogenic seizure. It is important and necessary to make the diagnosis as soon as possible in order to rapidly begin appropriate treatment including psychotherapy. In fact, the long-term prognosis in children is better than in the adult population. Associated risk factors, such as anxiety as reported in the present case, have to be sought. Recognizing psychogenic seizures will thus avoid their fixation in the child's personality and the risk of inappropriate and escalating treatments leading to iatrogenic complications.

Topics: Anticonvulsants; Child; Diagnosis, Differential; Electroencephalography; Fructose; Humans; Male; Psychophysiologic Disorders; Psychotherapy; Seizures; Status Epilepticus; Topiramate; Treatment Outcome

We report about a patient (66 years) who was referred to our psychiatric hospital because of a progressive confusional state with acute onset. The colleagues of the referring psychiatric hospital considered a first manic episode as the cause of the symptoms and under therapy with haloperidol the confusional state had shown a progression.The clinical examination's findings were a mild central facial paresis on the right side and a mild hemiparesis on the right side with elevated reflex levels.The patient was disoriented, he had cognitive and mnestic deficits. His reasoning was slowed, incoherent and perseverating. The patient had a slight euphoria.An EEG recording showed a continuous regional EEG-seizure pattern. In combination with the clinical symptoms we diagnosed a nonconvulsive status epilepticus. Under anticonvulsive treatment with Lorazepam and Valproic acid the status epilepticus sustended but a control EEG recording showed signs of a Valproate-encephalopathy. Under treatment with Topiramate symptoms ameliorated but due to a vascular dementia the patient still showed fluctuating symptoms of cognitive and mnestic disturbances.

Topics: Affect; Aged; Anticonvulsants; Antipsychotic Agents; Brain Edema; Confusion; Delirium; Dibenzothiazepines; Drug Substitution; Drug Therapy, Combination; Electroencephalography; Frontal Lobe; Fructose; Humans; Lorazepam; Magnetic Resonance Imaging; Male; Mental Status Schedule; Neurologic Examination; Quetiapine Fumarate; Referral and Consultation; Signal Processing, Computer-Assisted; Status Epilepticus; Topiramate; Valproic Acid

Refractory status epilepticus (RSE) is the most severe manifestation of status epilepticus (SE), often requiring intensive care and therapeutic coma. It is associated with prolonged intensive care unit (ICU) and hospital stays, as well as increased morbidity and mortality. Treatment involves both intravenous anaesthetics and antiepileptic drugs (AEDs) that can be administrated intravenously, by nasogastric tube or by percutaneous endoscopic gastrostomy. Experience with some of the newer AEDs for the treatment of RSE is restricted and higher-class evidence regarding tolerability and efficacy is lacking. Topiramate is a potent broad-spectrum AED with several modes of action, including blockade of the ionotropic glutamatergic AMPA receptor, which is likely to be an important mechanism for the treatment of SE. While there is no commercially available intravenous formulation, topiramate can be administered enterally, which may make it suitable for the treatment of RSE.. The objective of this study was to evaluate the tolerability, safety profile and efficacy of adjunctive and enterally administered topiramate in patients with RSE.. A medical chart review was performed of all consecutive patients treated for RSE between August 2004 and December 2011 at the ICU of the University Hospital Basel (Basel, Switzerland).. 113 (43%) of all consecutive 268 patients with SE developed RSE. Of those, 35 (31%) were treated with topiramate. Median age was 60.5 years. Topiramate was used as an add-on treatment after 1-6 (median 4) prior administered AEDs had failed. It was introduced after a median of 2 (range 2-23) days for a duration of 1-24 (median 3) days. The response rate after topiramate administration as the third AED was 86% (6/7 patients), and remained stable at 67% after administration as the fourth, fifth, sixth or seventh AED when the groups of successfully and probably successfully treated patients were pooled. Overall, RSE was terminated in 71% of patients within 72 hours after first administration of topiramate, in 9% of patients, within 24 hours (none in the 800 mg/day group; 9% in the 400-799 mg/day group; and 11% in the <400 mg/day group). Mortality was 31% and was not strictly dependent on failure to terminate RSE, but also on the underlying aetiology of RSE. There were no serious or fatal adverse events directly attributable to topiramate. Adverse effects included slight hyperchloremic acidosis and hyperammonemia (all associated with co-medication with valproic acid).. Treatment with enterally administered topiramate was feasible, well tolerated and had a good safety profile in patients with RSE in this observational, single-centre, cohort study. Refractory SE was terminated in the majority of patients within 3 days after initiation of topiramate. Prospective studies are warranted to further evaluate topiramate for the treatment of RSE.

Topics: Anesthetics; Anticonvulsants; Cohort Studies; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Therapy, Combination; Female; Fructose; Gastrostomy; Humans; Intubation, Gastrointestinal; Male; Medical Records; Middle Aged; Retrospective Studies; Status Epilepticus; Topiramate; Treatment Outcome

Status epilepticus is a common neurological emergency in childhood and associated with significant morbidity and mortality. Status epilepticus (SE) has been defined as continuous seizure activity lasting more than 30 min or 2 or more seizures in this duration without gaining consciousness between them. However, the operational definition has brought the time down to 5 min. Management can be broadly divided into initial stabilization, seizure termination, and evaluation and treatment of the underlying cause. Diagnostic evaluation and seizure control should be achieved simultaneously to improve outcome. Seizure termination is achieved by pharmacotherapy. Benzodiazepines are the first line drugs for SE. Commonly used drugs include lorazepam, diazepam, and midazolam. In children without an IV access, buccal or nasal midazolam or rectal diazepam can be used. Phenytoin as a second line agent is usually indicated when seizure is not controlled after one or more doses of benzodiazepines. If the seizures continue to persist, valproate, phenobarbitone or levetiracetam is indicated. Midazolam infusion is useful in refractory status epilepticus. Thiopentone, propofol or high dose phenobarbitone are considered for treatment of refractory status epilepticus. Prolonged SE is associated with higher morbidity and mortality. Long term neurological sequelae include epilepsy, behavioural problems, cognitive decline, and focal neurologic deficits.

Topics: Anticonvulsants; Benzodiazepines; Child; Clinical Protocols; Fructose; GABA Modulators; Humans; Ketamine; Levetiracetam; Midazolam; Pentobarbital; Phenobarbital; Phenytoin; Piracetam; Propofol; Status Epilepticus; Thiopental; Topiramate; Valproic Acid

We evaluated a topiramate (TPM) regimen for treating refractory status epilepticus in the largest pediatric series, reported to date.. Fourteen patients received TPM via the nasogastric route. Initially, all patients received TPM as a 5 mg/kg loading dose followed by 5 mg/kg/day in two doses as maintenance. Thereafter, patients were divided into three groups based on the response to TPM therapy and seizure cessation time (full responder, partial responder, and nonresponder). Four patients received only thiopental, two received thiopental, and high-dose midazolam, one received thiopental, high-dose midazolam, and propofol, two received only propofol, one received propofol, and high-dose midazolam and four patients were on a high-dose midazolam infusion.. The median time to seizure cessation was 5.5 h (range 2-48 h). Nine patients were full responders, three were partial responders, and two were nonresponders At follow-up, six patients were weaned successfully from thiopental, two patients from high-dose midazolam and three patients from propofol. Three patients developed mild metabolic acidosis during TPM theraphy.. Most of the patients responded to this treatment which was well tolerated. So we recommended its use for terminating refractory status epilepticus in children.

Topics: Anticonvulsants; Child; Child, Preschool; Female; Follow-Up Studies; Fructose; Humans; Infant; Male; Status Epilepticus; Topiramate; Treatment Outcome

Topics: Adolescent; Anticonvulsants; Female; Fructose; Humans; Mucolipidoses; Neuraminidase; Status Epilepticus; Topiramate; Treatment Outcome

We report the case of a 21-year-old man with idiopathic generalized epilepsy who ingested about 8,000 mg of topiramate (TPM) in a suicide attempt. On admission to the hospital he had a nonconvulsive status epilepticus and received 4 mg lorazepam i.v. He recovered rapidly despite an initial TPM concentration of 144.6 microg/ml. To our knowledge, this is the first report of a patient who survived such a high TPM concentration. The case indicates that nonconvulsive status epilepticus could be a manifestation of TPM intoxication.

Topics: Drug Overdose; Fructose; Humans; Male; Status Epilepticus; Suicide, Attempted; Topiramate; Young Adult

Topiramate is primarily renally eliminated and requires dosage adjustment based upon renal function. While there is data to suggest drug removal during intermittent hemodialysis (IHD), little is known regarding its clearance and dosing during continuous renal replacement therapy (CRRT).. We describe a 59-year-old man with refractory status epilepticus who was started on continuous venovenous hemodiafiltration (CVVHDF) for acute renal failure while receiving topiramate with a series of serum concentrations to assess for removal during CVVHDF.. Our data suggest clinically important amounts of topiramate are removed by CRRT, and higher topiramate dosage may be needed for these patients instead of the current recommended 50% of normal dosage. Unfortunately, there is no antiepileptic drug dosing recommendation when used during CRRT due to the paucity of data. This case highlights a need for research evaluating the effect of CRRT on AED elimination in order to optimize therapy for seizure control.

Topics: Anticonvulsants; Coma; Drug Resistance; Electroencephalography; Fatal Outcome; Fructose; Glasgow Coma Scale; Hemofiltration; Humans; Kidney Function Tests; Male; Middle Aged; Status Epilepticus; Topiramate

In this study we investigated the effectiveness of two antiepileptic drugs: riluzole and topiramate against pilocarpine-induced seizures, which are considered to be a model of intractable epilepsy commonly used to investigate the antiepileptic effect of drugs and mechanisms of epileptogenesis. Seizures and status epilepticus were induced by pilocarpine in adult male Wistar rats. Riluzole (1-4mg/kg) administered intraperitoneally before pilocarpine dose-dependently protected rats against seizures with the anticonvulsant ED(50) value (50% effective anticonvulsant dose) of 1.8 (1.3-2.6)mg/kg. In contrast, riluzole at 8 and 12mg/kg administered after the onset of pilocarpine-induced seizures affected neither status epilepticus nor mortality of rats. Topiramate significantly enhanced convulsive action of pilocarpine, lowering the convulsant CD(50) value (50% effective convulsant dose) of pilocarpine from 350.8 (329.2-373.8) to 246.4 (218.6-278.2)mg/kg. Riluzole (4mg/kg) lowered plasma and brain concentration of pilocarpine administered at a dose of 400mg/kg from 168.0+/-8.6 to 75.3+/-19.9microg/ml and from 193.7+/-6.6 to 97.0+/-26.1microg/g, respectively. Topiramate (200mg/kg) increased plasma and brain concentration of pilocarpine administered at a dose of 300mg/kg from 78.1+/-2.9 to 106.0+/-6.8microg/ml and from 138.4+/-5.0 to 155.2+/-5.1microg/g, respectively. It seems that both anticonvulsant effect exerted by riluzole and proconvulsant effect exerted by topiramate in pilocarpine model of seizures are due to a pharmacokinetic interaction. Therefore, we postulate that the concentration of pilocarpine should be measured routinely whenever the anticonvulsant effect of drugs is determined in the pilocarpine model of seizures.

Topics: Animals; Anticonvulsants; Brain; Chromatography, High Pressure Liquid; Convulsants; Drug Interactions; Fructose; Male; Pilocarpine; Rats; Rats, Wistar; Riluzole; Seizures; Status Epilepticus; Topiramate

We report a patient with a history of rare generalised tonic-clonic seizures and recurrent absence status who was diagnosed with a rare variant of idiopathic generalised epilepsy and absence status epilepsy. No other pathology was identified and MRI was normal. During a follow-up of 17 years, we recorded a single unilateral continuous, strictly subclinical, paroxysmal activity which lasted for at least several hours. No control was observed under treatment with phenobarbital, lamotrigine and topiramate. Absence status was aggravated with carbamazepine and generalised tonic-clonic seizures were not controlled with ethosuximide. Total seizure control was only possible with sodium valproate, which caused weight gain, and the patient has remained seizure-free for the past 10 years under 1,000 mg/d valproate and 200 mg/d topiramate. The recorded unilateral, long-lasting, subclinical spike-and-wave discharge is quite unusual for idiopathic generalised epilepsy and, in our opinion, occupies a transitional position between generalised and focal activity.

Topics: Adult; Anticonvulsants; Brain; Carbamazepine; Diagnosis, Differential; Dose-Response Relationship, Drug; Electroencephalography; Epilepsy, Tonic-Clonic; Female; Follow-Up Studies; Fructose; Humans; Lamotrigine; Phenobarbital; Secondary Prevention; Status Epilepticus; Topiramate; Treatment Outcome; Triazines; Valproic Acid; Weight Gain

Topiramate, an antiepileptic drug with multiple mechanisms of action, was assessed as a neuroprotective agent following status epilepticus. We administered topiramate or normal saline chronically beginning 1 hour after cessation of lithium pilocarpine-induced status epilepticus. Control animals not subjected to status epilepticus were also treated with topiramate or normal saline. Following completion of the topiramate treatment, animals were tested in the water maze to assess spatial learning and underwent in vivo single-cell place cell recordings. Spontaneous seizure frequency following status epilepticus in the topiramate-treated rats was similar to that in the rats treated with saline. Following status epilepticus, rats had profound deficits in water maze performance and place cell function. Rats subjected to status epilepticus and treated with topiramate were also severely impaired in the water maze, but performed slightly better than rats treated with saline. Following status epilepticus, topiramate-treated rats did not differ from rats treated with normal saline in the platform switch, a test of prefrontal function. Although place cell firing patterns were similar in both the topiramate- and saline-treated rats, rats treated with topiramate had higher information content scores than rats treated with saline. Topiramate-treated animals had less supragranular sprouting following status epilepticus than nontreated rats. Control animals treated with topiramate did not differ from saline-treated controls on any measures. Taken together, this study shows that topiramate administered following status epilepticus has modest neuroprotective effects.

Topics: Animals; Anticonvulsants; Convulsants; Electrodes, Implanted; Electroencephalography; Electrophysiology; Fructose; Hippocampus; Lithium Chloride; Male; Maze Learning; Neurons; Psychomotor Performance; Rats; Rats, Sprague-Dawley; Status Epilepticus; Topiramate

Refractory status epilepticus is a catastrophic illness of the central nervous system, with a mortality rate that reaches 50%. We report three patients admitted with refractory status epilepticus: a 24 year-old male that discontinued antiepileptic medications, a 46 year-old male with a focal epilepsy secondary to an encephalitis that discontinued medications due to gastrointestinal problems and a 59 year-old male with an ischemic encephalopathy AH were treated with topiramate, delivered through a nasogastric tube with a good response.

Topics: Administration, Oral; Anticonvulsants; Fructose; Humans; Hypoxia-Ischemia, Brain; Male; Middle Aged; Patient Dropouts; Status Epilepticus; Topiramate; Young Adult

Topics: Child; Fructose; Humans; Male; Status Epilepticus; Topiramate

Temporal lobe epilepsy is characterized by a progressive loss of memory capacities, due to sclerosis and functional impairment of mesiotemporal brain areas. We have shown recently that topiramate (TPM) dose-dependently protects hippocampal CA1 and CA3 neurons during initial status epilepticus in the rat pilocarpine model of temporal lobe epilepsy by inhibition of mitochondrial transition pore opening. In the present study, in order to evaluate possible positive effects of the treatment on learning and memory, we investigated water maze performance of rats receiving different dosages of TPM (20 and 100 mg/kg) after 40 min and 4 mg/kg diazepam after 160 min of pilocarpine-induced status epilepticus in relation to performance of animals receiving 4 mg/kg diazepam after 40 min of SE, and to performance of sham-treated control animals. Unexpectedly, 20 but not 100 mg/kg TPM significantly extenuated short-term memory deficits. While neuroprotective effects of TPM were observed in hippocampal CA subfields of animals treated with 100 mg/kg TPM, cell loss in rats treated with 20 mg/kg TPM was indistinguishable from animals receiving diazepam only. The present results indicate a negative dose-dependency of memory-saving effects of TPM applied during status epilepticus apparently dissociated from hippocampal neuroprotection.

Topics: Animals; Anticonvulsants; Diazepam; Disease Models, Animal; Dose-Response Relationship, Drug; Fructose; Hippocampus; Male; Maze Learning; Memory; Neurons; Neuroprotective Agents; Pilocarpine; Rats; Rats, Wistar; Status Epilepticus; Swimming; Topiramate; Video Recording; Water

To try to identify the critical structures during epileptogenesis, we used the lithium-pilocarpine model that reproduces most clinical and neuropathological features of temporal lobe epilepsy (TLE). We used imaging techniques as well as a disease modifying approach and pharmacological strategy. With [14C]-2-deoxyglucose autoradiography, we assessed changes in cerebral glucose utilization. T2-weighted magnetic resonance imaging (MRI, 4.7 T) allowed follow-up of structures involved in epileptogenesis. A potential disease-modifying effect was studied using preconditioning with brief seizures (amygdala kindling, maximal electroshocks) and pharmacological strategies including vigabatrin (250 mg/kg), caffeine (0.3 g/L in drinking water), topiramate (10-60 mg/kg), pregabalin (50 mg/kg followed by 10 mg/kg), or RWJ-333369 (10-120 mg/kg). In adult and PN21 rats that became epileptic, entorhinal, and piriform cortices were the initial structures exhibiting significant signal changes on MRI scans, from 6 h after status epilepticus (SE) onset, reflecting neuronal death. In PN21 rats that did not become epileptic, no signal occurred in parahippocampal cortices. In hippocampus, MRI signal change appeared 36-48 h after SE, and progressively worsened to sclerosis. During the latent and chronic phases, the metabolic level in the hilus of adult and PN21 epileptic rats was normal although neuronal loss reached 60-75%. Protection limited to CA1 and/or CA3 (caffeine, topiramate, vigabatrin, amygdala kindling) did not affect the latency to spontaneous seizures. Protection limited to the entorhinal and piriform cortices (pregabalin) delayed epileptogenesis. The combined protection of Ammon's horn and parahippocampal cortices (RWJ-333369) prolonged the latency before the onset of seizures in a dose-dependent manner or, in some cases, prevented the epilepsy. The entorhinal and piriform cortices are critically involved in the early phase of the epileptogenesis while the hilus may initiate and/or maintain epileptic seizures. Pharmacological protection of the basal cortices is necessary for a beneficial disease-modifying effect but this must be combined with protection of the hippocampus to prevent epileptogenesis in this model of TLE.

Topics: Animals; Animals, Newborn; Anticonvulsants; Autoradiography; Cell Count; Cerebral Cortex; Deoxyglucose; Disease Models, Animal; Electroencephalography; Electroshock; Entorhinal Cortex; Epilepsy, Temporal Lobe; Fructose; Glucose; Hippocampus; Kindling, Neurologic; Lithium Chloride; Magnetic Resonance Imaging; Olfactory Pathways; Pilocarpine; Rats; Rats, Sprague-Dawley; Status Epilepticus; Topiramate; Vigabatrin

We studied the effects of treating status epilepticus (SE) induced by lithium and pilocarpine at postnatal day 15 (P15) or 28 (P28), on the severity of acute SE and of SE-induced epileptogenesis. Rats received topiramate (10 or 50 mg/kg, IP) or diazepam (5 mg/kg, IP) 20, 40 or 70 min after pilocarpine, and three months after SE 24-h video/EEG recordings were obtained for one (P28) or two weeks (P15) continuously. In P15 rats, topiramate did not modify the course of SE, yet treatment at 20 or 40 min completely prevented the development of spontaneous recurrent seizures (SRS) while later treatment (70 min) was partially effective in reducing the severity and frequency of SRS. Diazepam was effective against acute SE at all time points tested. Early (20 min) but not late treatment with diazepam had the effect of reducing the frequency and severity of SRS. In P28 rats, both drugs reduced the cumulative seizure time. Early treatment (20 min) with either drug reduced the incidence of chronic epilepsy. Late treatment (40/70 min) did not alter the incidence of SRS, but decreased their frequency. This study demonstrates that, in the treatment of SE, anticonvulsant and antiepileptogenic effects can be dissociated in a development-specific manner: topiramate was antiepileptogenic without being an effective anticonvulsant in P15 animals at the doses tested. Diazepam, on the other hand, was a better anticonvulsant than an antiepileptogenic agent in the P15 animals at the dose tested. Such effects were not seen in the older animals.

Topics: Animals; Anticonvulsants; Atropine; Diazepam; Dose-Response Relationship, Drug; Electroencephalography; Fructose; Pilocarpine; Rats; Rats, Wistar; Status Epilepticus; Topiramate

To describe three cases of refractory status epilepticus (RSE) in children responsive to topiramate (TPM).. Patients with SE refractory to therapeutic doses of at least two antiepileptic medications were given TPM, 10 mg/kg/d, for 2 consecutive days, followed by maintenance doses of 5 mg/kg/d.. This protocol has been used in three cases of RSE at our institution. In each case, SE was aborted within 21 h of the initial dose of TPM. Two patients avoided pharmacologic coma, and one was rapidly weaned from continuous benzodiazepine infusion.. Our experience indicates that TPM loading can be effective in the treatment of RSE in children.

Topics: Age Factors; Anticonvulsants; Child; Child, Preschool; Drug Administration Schedule; Drug Resistance; Female; Fructose; Humans; Infant; Male; Status Epilepticus; Topiramate; Treatment Outcome

Lithium-pilocarpine induces status epilepticus (SE), leading to extensive damage and spontaneous recurrent seizures (SRS). Neuroprotective and antiepileptogenic effects of topiramate (TPM) associated with diazepam (DZP) were investigated in this model. SE was induced by LiCl and pilocarpine. TPM (10, 30 or 60 mg/kg) was injected at the onset of SE and 10h later and DZP (2.5 and 1.25mg/kg) at 2 and 10h after SE. TPM treatment was continued twice daily for 6 days. Other rats received two injections of DZP on the day of SE. Cell counting was performed on thionine-stained sections 14 days after SE and after 2 months of epilepsy. Occurrence and frequency of SRS were video-recorded. The MRI T2-weighted signal was quantified in hippocampus and ventral cortices. DZP-TPM treatment induced partial neuroprotection in CA1 and hilus, and tended to increase the percentage of rats with protected neurons in layer III/IV of the ventral entorhinal cortex. The latency to and frequency of SRS were not modified by DZP-TPM. T2-weighted signal was decreased in hippocampus 3 days after SE at all TPM doses and in ventral hippocampus after epilepsy onset. In conclusion, although DZP-TPM treatment was able to partially protect two areas critical for epileptogenesis, the hippocampus and ventral entorhinal cortex, it was not sufficient to prevent epileptogenesis.

Topics: Animals; Anticonvulsants; Diazepam; Disease Models, Animal; Drug Therapy, Combination; Electroencephalography; Epilepsy, Temporal Lobe; Fructose; Hippocampus; Lithium; Magnetic Resonance Imaging; Male; Pilocarpine; Rats; Rats, Sprague-Dawley; Status Epilepticus; Topiramate

Topics: Anticonvulsants; Antipsychotic Agents; Autistic Disorder; Caregivers; Child; Developmental Disabilities; Epilepsy; Female; Foster Home Care; Fructose; Humans; Impulsive Behavior; Mental Status Schedule; Psychological Tests; Risperidone; Status Epilepticus; Topiramate; Valproic Acid

The purpose of this study was to assess the effectiveness and tolerability of topiramate (TPM) as add-on therapy in children with Dravet syndrome and considered unsatisfactorily controlled using stiripentol. All the 36 patients having been treated with TPM in our centre in 2001 were retrospectively evaluated. Seventy percent of them still received stiripentol when TPM was introduced. The association of both drugs did not need any particular adaptation of dosages. The mean TPM follow-up was 13.3 months (4-25 months) and the mean optimal TPM dose was 3.2 mg/kg/d (0.6-9.2 mg/kg/d). Twenty eight children (78 %) showed more than 50 % reduction in the frequency of generalized tonic-clonic seizures and status epilepticus (SE), whereas 8 % had more than 50 % increase. Six patients (17 %) remained seizure-free for at least 4 months. The most frequently reported side-effects were gastrointestinal and behavioural disturbances. TPM had to be stopped in 17 % of patients, because of poor tolerability and/or lack of efficacy. Topiramate seems therefore to be helpful in Dravet syndrome, even in patients not satisfactorily controlled by stiripentol. Both drugs can be easily and safely associated.

Topics: Anticonvulsants; Dioxolanes; Drug Therapy, Combination; Electroencephalography; Epilepsies, Myoclonic; Epilepsy, Tonic-Clonic; Female; Follow-Up Studies; Fructose; Humans; Infant; Male; Retrospective Studies; Seizures, Febrile; Status Epilepticus; Topiramate; Treatment Outcome

Potential antiepileptic drugs (AEDs) are typically screened on acute seizures in normal animals, such as those induced in the maximal electroshock and pentylenetet-razole models. As a proof-of-principle test, the present experiments used spontaneous epileptic seizures in kainate-treated rats to examine the efficacy of topiramate (TPM) with a repeated-measures, crossover protocol.. Kainic acid was administered in repeated low doses (5 mg/kg) every hour until each Sprague-Dawley rat experienced convulsive status epilepticus for >3 h. Six 1-month trials (n = 6-10 rats) assessed the effects of 0.3-100 mg/kg TPM on spontaneous seizures. Each trial involved six pairs of TPM and saline-control treatments administered as intraperitoneal injections on alternate days with a recovery day between each treatment day. Data analysis included a log transformation to compensate for the asymmetric distribution of values and the heterogeneous variances, which appeared to arise from clustering of seizures.. A significant effect of TPM was observed for 12 h (i.e., two 6-h periods) after a 30-mg/kg injection, and full recovery from the drug effect was complete within 43 h. TPM exerted a significant effect at doses of 10, 30, and 100 mg/kg, and the effects of TPM (0.3-100 mg/kg) were dose dependent.. These data suggest that animal models with spontaneous seizures, such as kainate- and pilocarpine-treated rats, can be used efficiently for rapid testing of AEDs with a repeated-measures, crossover protocol. Furthermore, the results indicate that this design allows both dose-effect and time-course-of-recovery studies.

Topics: Animals; Anticonvulsants; Chronic Disease; Cross-Over Studies; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Epilepsy; Fructose; Injections, Intraperitoneal; Kainic Acid; Pilocarpine; Rats; Rats, Sprague-Dawley; Research Design; Sodium Chloride; Status Epilepticus; Topiramate

Topiramate was safely administered to two young children with refractory partial status epilepticus via nasogastric tube in rapid titration up to a very high total daily dose. An excellent clinical response occurred in both cases. Reaching high daily doses of topiramate within days allowed for safe discontinuation of other antiepileptic drugs in both patients. Given the high efficacy of rapidly titrated topiramate in our patients, this medication may be useful in some cases of pediatric refractory partial status epilepticus. However, more clinical studies on this therapeutic approach are needed to establish the precise role of topiramate in status epilepticus in children.

Topics: Anticonvulsants; Child, Preschool; Dose-Response Relationship, Drug; Female; Fructose; Humans; Male; Status Epilepticus; Topiramate

Refractory temporal lobe epilepsy (TCE) shows a unique type of hippocampal damage, referred to as hippocampal sclerosis. The mechanisms underlying drug-refractoriness in TCE are poorly understood, which may be connected with pharmacoresistance to antiepileptic drugs (AEDs). Some studies show that expression of the multidrug resistance gene (mdr1a and mdr1b) and p-glycoprotein encoded by mdr1a and mdr1b are high in the brain, especially in the hippocampus, and the expression may lead to reduction of AEDs concentration in the brain. But most of these studies focused on acute epileptic activity shortly after status epilepticus (SE), spontaneous seizures are seldom studied. The authors used a rat model of kainic acid induced spontaneous seizures to investigate expression of mdr1a and mdr1b mRNA, and explore whether topiramate (TPM) affects expression of mdr1a and mdr1b in the hippocampus.. Seizures were induced by intraperitoneal injection of 10 mg/kg kainic acid at postnatal day 28. Control rats were injected with sodium chloride. All rats were divided into 4 groups 1 week after spontaneous seizures developed: status epilepticus complicated with spontaneous seizures (SE, n = 8) group, status epilepticus complicated with spontaneous seizures treated with TPM (SE + TPM, n = 9) group, spontaneous seizures without status epilepticus (N-SE, n = 7) group, spontaneous seizures without status epilepticus treated with TPM (N-SE + TPM, n = 8) group, control (n = 7) group and control treated with TPM (control + TPM, n = 7) group. The treated rats were given therapeutic dose of TPM (25 mg/kg). All the rats were killed on the 42nd day of administration. The mdr1a and mdr1b mRNAs in the hippocampus were measured by RT-PCR.. Expression of mdr1a and mdr1b mRNA in the hippocampus increased significantly in the SE + TPM group, SE group and N-SE + TPM group compared with control group (P < 0.001 or < 0.05). The mRNA in SE + TPM group increased significantly compared with the SE group, too (P < 0.01). The mdr1a and mdr1b mRNA expression in the hippocampus in control + TPM and N-SE groups did not change.. Frequent seizures, especially status epilepticus resulted in overexpression of mdr1a and mdr1b mRNAs in the hippocampus. The drug-refractoriness mechanism in TCE may be related to overexpression of mdr1a and mdr1b mRNAs. TPM could enhance the expression of mdr1a and mdr1b mRNAs in the hippocampus. Seizure activity and TPM are likely to be the main determinant in enhancing mdr1a and mdr1b mRNA expression in epilepsy.

Topics: Animals; Anticonvulsants; ATP Binding Cassette Transporter, Subfamily B, Member 1; Fructose; Hippocampus; Kainic Acid; Rats; RNA, Messenger; Seizures; Status Epilepticus; Topiramate

The lithium-pilocarpine model reproduces the main characteristics of human temporal lobe epilepsy. After status epilepticus (SE), rats exhibit a latent seizure-free phase characterized by development of extensive damage in limbic areas and occurrence of spontaneous recurrent seizures. Neuroprotective and antiepileptogenic effects of topiramate were investigated in this model. SE was induced in adult male rats by LiCl (3 mEq/kg) followed 20 h later by pilocarpine (25 mg/kg). Topiramate (10, 30, or 60 mg/kg) was injected at 1 and 10 h of SE. Injections were repeated twice a day for six additional days. Another group received two injections of diazepam on the day of SE and of vehicle for 6 days. Neuronal damage was assessed at 14 days after SE by cell counting on thionin-stained sections. Occurrence of spontaneous recurrent seizures (SRS) was videorecorded for 10 h per day in other groups of rats. In diazepam-treated rats, the number of neurons was dramatically reduced after SE in all subregions of hippocampus and layers II-IV of ventral cortices. At all doses, topiramate induced a 24 to 30% neuroprotection in layer CA1 of hippocampus (p < 0.05). In CA3b, the 30-mg/kg dose prevented neuronal death. All rats subjected to SE became epileptic. The latency (14-17 days) to and frequency of SRS were similar in topiramate- and diazepam-treated rats. The high mortality in the 30 mg/kg topiramate group (84%) was possibly the result of interaction between lithium and topiramate. In conclusion, topiramate displayed neuroprotective properties only in CA1 and CA3 that were not sufficient to prevent epileptogenesis.

Topics: Animals; Blood Gas Analysis; Cell Death; Cerebral Cortex; Electroencephalography; Fructose; Hippocampus; Hydrogen-Ion Concentration; Lithium; Male; Neurons; Neuroprotective Agents; Pilocarpine; Rats; Rats, Sprague-Dawley; Status Epilepticus; Topiramate

Topics: Anticonvulsants; Benzodiazepines; Carbonic Anhydrases; Fructose; Humans; Receptors, GABA-A; Status Epilepticus; Topiramate

To evaluate the antiepileptic and neuroprotective properties of topiramate (TPM) alone and with coadministration of the N-methyl-D-aspartate (NMDA)-receptor antagonist budipine in a rat model of refractory status epilepticus.. Male Sprague-Dawley rats had electrodes implanted into the perforant path and dentate granule cell layer of the hippocampus under halothane anesthesia. Approximately 1 week after surgery, the perforant path of each animal was electrically stimulated for 2 h to induce self-sustaining status epilepticus. Successfully stimulated rats were given intraperitoneally vehicle (n = 6), TPM (20-320 mg/kg; n = 28), budipine (10 mg/kg; n = 5), or budipine (10 mg/kg) and TPM (80 mg/kg; n = 6) 10 min after the end of the stimulation and monitored behaviorally and electroencephalographically for a further 3 h. The animals were killed 14 days later, and histopathology was assessed.. Neither budipine alone nor TPM at any dose terminated status epilepticus. Despite this, TPM resulted in various degrees of neuroprotection at doses between 40 and 320 mg/kg. Coadministration of budipine with TPM terminated the status epilepticus in all rats. This combination also significantly improved the behavioral profile and prevented status-induced cell death compared with control.. Budipine and TPM are an effective drug combination in stopping self-sustained status epilepticus, and TPM alone was neuroprotective, despite the continuation of seizure activity.

Topics: Animals; Anticonvulsants; Cell Death; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Electric Stimulation; Electrodes, Implanted; Electroencephalography; Fructose; Humans; Male; Neurons; Neuroprotective Agents; Perforant Pathway; Piperidines; Rats; Rats, Sprague-Dawley; Receptors, N-Methyl-D-Aspartate; Status Epilepticus; Topiramate

For the antiepileptic drug (AED) topiramate (TPM), neuroprotective effects have been reported in models of focal cerebral ischemia and experimental status epilepticus, but the putative mechanism of action has remained elusive.. We studied the effects of TPM on mitochondrial function in the pilocarpine rat model of chronic epilepsy and in isolated mitochondria from rat brain.. TPM treatment in status epilepticus at doses ranging from 20 to 100 mg/kg considerably improved the survival of rats and improved CA1 and CA3 pyramidal cell survival in a dose-dependent manner. This treatment increased the activity of mitochondrial respiratory chain complex I in the CA1 and CA3 pyramidal subfields and resulted in lower seizure frequencies in chronic epileptic rats. In vitro investigations of the action of TPM on isolated rat brain mitochondria ruled out any direct effects of the drug on mitochondrial oxidative phosphorylation but revealed a protective effect on hippocampal mitochondria against an external calcium challenge. This can explain its observed neuroprotective action in the concentration range tested. The in vitro effects of TPM on the calcium handling of isolated brain mitochondria was found to be comparable to the action of cyclosporin A.. The neuroprotective action of TPM seems to be directly related to its inhibitory effect on the mitochondrial permeability transition pore.

Topics: Animals; Brain; Cell Survival; Cyclosporine; Disease Models, Animal; Dose-Response Relationship, Drug; Epilepsy; Fructose; Hippocampus; In Vitro Techniques; Ion Channels; Kindling, Neurologic; Male; Mitochondria; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Neuroprotective Agents; Oxidative Phosphorylation; Pilocarpine; Pyramidal Cells; Rats; Rats, Wistar; Status Epilepticus; Topiramate

Status epilepticus (SE) is a life-threatening medical condition associated with significant morbidity and mortality that requires urgent medical intervention. Although several agents are available to treat SE, they occasionally fail to abort seizure activity. Topiramate (TPM) was anecdotally reported to be effective in adult patients with refractory SE. In this study, we evaluated the efficacy of TPM administered to children with this condition.. We retrospectively reviewed the pediatric SE database at the University of Michigan Medical Center and identified three children with refractory SE who were treated with TPM. Those children failed to respond to treatment with benzodiazepines, phenytoin, phenobarbital, midazolam, or pentobarbital. Additional treatment with TPM was administered by nasogastric tube. All patients were continuously monitored by 21-channel digital EEG machines, and the diagnosis of SE was made by a board-certified neurophysiologist.. The ages of the three children were 4.5 months, 34 months, and 11 years. TPM was initiated at 2 mg/kg/day in two children and at 3 mg/kg/day in the third. The status was terminated in all three children within 24 h of maintenance therapy with TPM at 5-6 mg/kg/day.. These results support the potential efficacy of TPM for children with refractory SE. Larger prospective series are needed to confirm those results.

Topics: Child; Child, Preschool; Female; Fructose; Humans; Infant; Male; Retrospective Studies; Status Epilepticus; Topiramate

The goal of this study was to report the effectiveness of topiramate in treating status epilepticus.. Three patients with status epilepticus were treated with topiramate 500 mg twice daily for 2-5 days, with the dose gradually tapered thereafter to 200 mg twice daily. The patients' clinical status and EEG recordings were followed.. Patient 1 was admitted for subacute encephalopathy that was complicated by secondarily generalized status epilepticus resistant to lorazepam, fosphenytoin, and pentobarbital coma. Topiramate was added and, 2 days later, pentobarbital was tapered with no recurrence of ictal discharges as the patient improved clinically. Patient 2 had end-stage liver disease and was hospitalized for peritonitis, and his course was complicated by partial status epilepticus. Topiramate was started and, 2 days later, his mental status improved as repeat EEG showed no further ictal discharges although periodic epileptiform discharges were seen in the left centroparietal area. The patient later died from complications of variceal bleeding. Patient 3 suffered cardiopulmonary arrest, and developed postanoxic seizures, which did not respond to lorazepam, fosphenytoin, valproate, and propofol coma as continuous EEG recordings showed recurrent generalized ictal discharges. Two days after topiramate was started, propofol was tapered and discontinued and EEG showed generalized slow wave activity and no ictal discharges. The patient was discharged to another facility 12 days later.. Topiramate was effective in treating two patients with refractory generalized status epilepticus and one with complex partial status epilepticus. It should therefore be considered as an option in these situations, especially when other medications cannot be used.

Topics: Adult; Aged; Anticonvulsants; Dose-Response Relationship, Drug; Electroencephalography; Fructose; Heart Arrest; Humans; Male; Middle Aged; Status Epilepticus; Topiramate; Treatment Outcome

Topics: Anticonvulsants; Child, Preschool; Electroencephalography; Fructose; Humans; Male; Sleep; Status Epilepticus; Topiramate

Prolonged seizures are associated with injury to vulnerable neurons, particularly in the hippocampus. Identification of compounds that attenuate injury after prolonged seizures could be of value in the management of refractory status epilepticus. We hypothesized that topiramate, an anticonvulsant with multiple mechanisms of action, would attenuate hippocampal neuronal injury when given after experimental status epilepticus. Limbic status epilepticus was induced in adult male Wistar rats for 140 min by unilateral hippocampal electrical stimulation. Rats then received intraperitoneal injections of either vehicle (n=6) or topiramate at 20 mg/kg (n=6), 40 mg/kg (n=7) or 80 mg/kg (n=7). Three days later, hippocampal sections were processed for neuronal degeneration using a silver impregnation stain. Seizure-induced damage was assessed by measuring the density of silver staining in hippocampal regions CA1, CA3 and dentate hilus. Administration of topiramate at each dose was associated with a significant reduction in staining density bilaterally in area CA1 and the dentate hilus. Reduction in staining density in area CA3 was seen contralateral to the side of stimulation at the two higher topiramate doses only. The results indicate that administration of topiramate after experimental status epilepticus can attenuate seizure-induced hippocampal neuronal injury.

Topics: Animals; Anticonvulsants; Electric Stimulation; Electroencephalography; Fructose; Functional Laterality; Hippocampus; Male; Nerve Degeneration; Neurons; Rats; Rats, Wistar; Status Epilepticus; Topiramate