Intravenous loading of valproate for epilepsy

Management of status epilepticus

Status epilepticus is a neurologic and medical emergency manifested by prolonged seizure activity or multiple seizures without return to baseline. It is associated with substantial medical cost, morbidity, and mortality. There is a spectrum of severity dependent on the type of seizure, underlying pathology, comorbidities, and appropriate and timely medical management. This chapter discusses the evolving definitions of status epilepticus and multiple patient and clinical factors which influence outcome. The pathophysiology of status epilepticus is reviewed to provide a better understanding of the mechanisms which contribute to status epilepticus, as well as the potential long-term effects. The clinical presentations of different types of status epilepticus in adults are discussed, with emphasis on the hospital course and management of the most dangerous type, generalized convulsive status epilepticus. Strategies for the evaluation and management of status epilepticus are provided based on available evidence from clinical trials and recommendations from the Neurocritical Care Society and the European Federation of Neurological Societies.

Efficacy and safety of intravenous valproate for status epilepticus: a systematic review

INTRODUCTION

The effectiveness of valproate (VPA) in the treatment of focal and generalized epilepsies is well established. The drug has a wide spectrum of action, good tolerability, and has been available as an injectable formulation since 1993. Despite the lack of class A evidence, it has been used extensively in various forms of status epilepticus (SE).

AIM

Our aim was to present a systematic review of data from randomized and non-randomized controlled trials to evaluate the efficacy and safety of intravenous VPA for the treatment of SE.

METHODS

Data sources included MEDLINE, back tracing of references in pertinent studies, and contact with the manufacturer of VPA (Sanofi-Aventis).

RESULTS

Overall, the search strategy yielded 433 results (425 MEDLINE, seven congress abstracts, one unpublished study); after excluding duplicate publications and case reports, 30 studies were identified (the earliest was published in 1993, the most recent in 2012); ten were controlled (six randomized controlled trials, four non-randomized controlled studies), and 20 uncontrolled trials (eight prospective observational studies, 12 retrospective case series). The cumulative literature describes the experiences of 860 patients with various forms of SE treated with intravenous VPA. The overall response rate to abrogate SE was 70.9% (601/848; 95% confidence interval [CI] 67.8-73.9). Response rates to intravenous VPA were better in children than in adults and did not differ between the SE types. The most commonly reported effective doses were between 15 and 45 mg/kg in bolus (6 mg/kg/min) followed by 1-3 mg/kg/h infusion. Safety studies of intravenous VPA administration in patients with SE showed a low incidence of adverse events overall (<10%), mainly dizziness, thrombocytopenia, and mild hypotension, which was independent of infusion rates. Of note, good cardiovascular and respiratory tolerability was observed in these studies, even at high doses and fast infusion rates (up to 30 mg/kg at 10 mg/kg/min), despite multiple morbidities or other antiepileptic drugs. The most serious concern relates to the possibility of acute encephalopathy, sometimes related to hepatic abnormalities or hyperammonemia.

CONCLUSIONS

The published experience is consistent with VPA being a safe and effective therapeutic option for patients with established SE who have previously failed conventional first-line treatment with benzodiazepines, but high-quality randomized controlled trials are needed to inform clinicians on its comparative effectiveness in SE.

The efficacy of intravenous sodium valproate and phenytoin as the first-line treatment in status epilepticus: a comparison study

Background

Status epilepticus (SE) is a serious neurological condition and requires prompt treatment. Sodium valproate has been used to treat SE successfully but its role as the first-line antiepileptic drug (AED) is still controversial. This study evaluated the efficacy of intravenous sodium valproate to determine if it is non-inferior to intravenous phenytoin in SE treatment.

Methods

Patients diagnosed as SE during 2003–2010 who were of an age of more than 15 years and received either intravenous sodium valproate or intravenous phenytoin as the first-line treatment were enrolled. Clinical characteristics and outcomes of SE were recorded and analyzed. The differences of outcomes between sodium valproate and phenytoin group were determined by descriptive statistics.

Results

During the study period, there were 37 and 17 SE patients who received intravenous phenytoin and intravenous sodium valproate as the first-line treatment, respectively. All patients received diazepam 10 mg intravenously as a rescue medication before starting the antiepileptic agents if uncontrolled except one patient in the sodium valproate group. There were no significant differences between the phenytoin and sodium valproate groups in all outcome variables including numbers of patients with clinically-controlled seizures, non-dependent patients, time to seizure control, and duration of hospitalization, and death. No serious cardiovasculars event such as hypotension occurred in either group.

Conclusion

Intravenous sodium valproate is non-inferior to intravenous phenytoin as the first-line treatment in SE with no significant cardiovascular compromises.

Efficacy and safety of intravenous sodium valproate versus phenobarbital in controlling convulsive status epilepticus and acute prolonged convulsive seizures in children: a randomised trial

Status epilepticus and acute prolonged seizures are the most commonly occurring neurological emergencies in children. Such events have high morbidity and mortality rates along with poor long-term outcomes, depending on their duration and causes. Therefore, such seizures warrant urgent treatment using appropriate doses of anticonvulsants. Benzodiazepines, phenobarbital, and phenytoin are the most commonly used anticonvulsants for controlling status epilepticus and acute prolonged seizures. However, these medications have several well-known adverse effects. Previous studies on both adults and children have shown the efficacy and safety of rapid infusion of valproate in controlling status epilepticus. However, few well-designed randomised trials have been carried out in children, and there remains a paucity of data regarding intravenous sodium valproate use in children. Therefore, our aim was to compare the efficacy and safety of rapid loading of valproate with those of intravenous phenobarbital in children with status epilepticus and acute prolonged seizures. Sixty children (30 in each group) with convulsive status epilepticus and acute prolonged seizures were enrolled and randomly assigned to receive either valproate or phenobarbital. The main outcome variable was termination of all convulsive activity within 20 min of starting anticonvulsant infusion. Intravenous rapid loading of valproate was successful in seizure termination in (27/30, 90%) of patients compared to phenobarbital (23/30, 77%) (p = 0.189). Clinically significant adverse effects occurred in 74% patients of the phenobarbital group and 24% patients of the valproate group (p < 0.001). In conclusion, rapid loading of valproate is effective and safe in controlling convulsive status epilepticus and acute prolonged convulsive seizures in children. Intravenous valproate should be considered as a suitable choice for terminating status epilepticus and acute prolonged seizures in children.

Pharmacokinetics and clinical application of intravenous valproate in Thai epileptic children

Roles of intravenous administration of valproate in status epilepticus and serial seizures are documented in adults and children. Pharmacokinetic parameters are necessary to predict the optimum therapeutic level after administration. A cross-sectional study to determine the pharmacokinetic parameters and safety of intravenous valproate for future application was conducted in Thai children from January to December 2008. There were eleven children, age-range 1-15 years (mean age 9.5 years) enrolled. Valproate of 15-20 mg/kg was administrated intravenously at the rate of 3 mg/kg/min, followed by 6 mg/kg every 6 h. Valproate level was determined prior to the initial dose and at ½, 1, 2, 4, 5, and 6 h postdose. Complete blood count, serum ammonia, and liver function tests were collected prior to the initial dose and at 6 h. Median loading dose was 19 mg/kg (range 15-20.5 mg/kg). Median maximum concentration at 30 min after infusion was 98.8 mcg/mL (range 67-161 mcg/mL). Median volume of distribution was 0.20 L/kg (range 0.15-0.53 L/kg). Median half-life was 9.5 h (range 4.4-24.2 h). Median clearance was 0.02 L/h/kg (range 0.01-0.05 L/h/kg). Six hours after initial dose, eight children did not have recurrent seizure. One child had brief seizure at 20 min after initial dose. Seizure recurred in two children at 4th and 5th hour. Asymptomatic transient elevation of serum ammonia was observed in two children. Volume of distribution of 0.20 L/kg could be applied for initial intravenous administration with a favorable efficacy.

Management of refractory status epilepticus at a tertiary care centre in a developing country

BACKGROUND

Refractory status epilepticus (RSE) is a common Neurological Emergency with increased mortality and morbidity in developing countries where facilities of intubation, adequate ventilation, Intensive Care Units (ICUs) and general anaesthesia are not ubiquitously available. Treatment protocols use antiepileptic drugs (AEDs) and need ICU facilities after failure of standard AEDs. Our aim was to see the response to two additional drugs in the armamentarium against refractory status, that is, valproate and levetiracetam.

METHODS

Patients with generalized RSE admitted in neurology and neurosurgery services at AIIMS during December 2006 to June 2008 were included in the study. The patients were allotted to two groups based on certain criteria. Demographic details, reason for delay, etiology precipitating status, ongoing AEDs therapy, duration of status, the time taken for cessation along with clinical, EEG and MRI correlates were noted. Outcome parameters were analyzed by an independent blinded observer.

RESULTS

82 patients with RSE were studied out of which 41 patients were given IV valproate (Group A) and 41 patients were given IV levetiracetam (Group B). Cessation of status failed in 13 patients in valproate group and 11 patients in levetiracetam group. Majority of the patients did not require ICU settings despite being classified as refractory.

CONCLUSION

RSE can be controlled with intravenous loading and maintenance of valproate or levetiracetam which do not cause respiratory depression, hypotension, need of intubation and ICU care. These must always be considered in a developing country scenario where ICU facilities are not always available or while transporting to centres where these facilities are available.

Safety of rapid intravenous loading of valproate

BACKGROUND

The introduction of IV valproic acid (VPA) has facilitated its use in situations where oral administration is not feasible. The present study was designed to evaluate the safety of administration of undiluted VPA (20 or 30 mg/kg/min) administered intravenously at rates of 6 or 10 mg/kg/min.

METHODS

Forty patients received a VPA loading dose (20 or 30 mg/kg) at 6 or 10 mg/kg/min. Heart rate (HR), mean arterial pressure (MAP), oxygen saturation, respiratory rate, and three lead ECG measurements were taken at baseline. Following dose administration the measurements were repeated at 2.5-min intervals for the first 20 min, then at 30, 45, 60 min, and 4 h. Local tolerance was defined as absence of irritation or phlebitis at the site of injection. Systemic tolerability was defined as absence of significant changes in vital signs and level of consciousness (LOC). Changes in vital signs and local intolerance scores were compared across time using repeated measures analysis of variance.

RESULTS

Rapid administration was well tolerated with no significant changes in HR (p=0.9) or MAP (p=0.7). Complaints of local irritation were transient, lasting less than 3 min in all patients with no indication of redness, irritation, or phlebitis. No patient exhibited a decline in the LOC.

CONCLUSIONS

Rapid administration of undiluted valproate is safe and well tolerated at infusion rate up to 10 mg/kg/min and doses of up to 30 mg/kg. The lack of serious cardiovascular, neurological, hepatic, or local adverse effects supports the use of VPA in emergent situations.

Safety of rapid intravenous valproate infusion in pediatric patients

In order to investigate the safety of rapidly infused intravenous valproate in children with seizures, the drug was administered to 18 patients (age range, 1-16 years) at doses ranging from 7.5 to 41.5 mg/kg and rates of 1.5 to 11 mg/kg per minute. Forty-eight intravenous valproate doses were administered during 19 hospital admissions (range, 1-16 doses per admission). Only one adverse event was reported; a 9-year-old male experienced burning at the infusion site while receiving 660 mg intravenous valproate at 6 mg/kg per minute. The patient tolerated three subsequent infusions (one of 330 mg and two of 165 mg) at the same rate with no further discomfort. Electrocardiogram results, available for 18 admissions, revealed no arrhythmias, bradycardias, or hypotensive episodes. No abnormal laboratory results were reported. Rapid intravenous valproate infusion appears to be safe in pediatric patients.

Intravenous valproate as an innovative therapy in seizure emergency situations including status epilepticus--experience in 102 adult patients

PURPOSE

The emergency treatment of seizures is an important practical issue, in particular the therapy of status epilepticus. Antiepileptic drugs for this condition should be easy to use, show rapid action, have a long-lasting antiepileptic effect, and have minimal cardiopulmonary and other side-effects. Unfortunately, none of the presently available medications such as phenytoin and barbiturates seems to have all of these four properties. Intravenous valproate became available some years ago and first experiences show promising safety data and efficacy results.

METHODS

We report a series of 102 adult patients who received standardized high dosage intravenous valproate in various emergency situations, including status epilepticus. The therapeutic goal was persistent seizure control, defined as successful interruption of clinical seizure activity within less than 15 min, followed by seizure freedom during intravenous therapy for at least 12h. All side effects were documented.

RESULTS

In 83/97 patients (85.6%) the therapeutic goal was achieved. Serious side effects were not documented in any patient. In particular there was no evidence of sedation, cardiorespiratory disturbances and hypotension as often seen in barbiturates and phenytoin. Mild side effects occurred in seven cases (6.9%).

CONCLUSIONS

The intravenous application of VPA seems to be an easy-to-use, safe and efficient formulation as an alternative to phenytoin in all seizure emergency situations including status epilepticus. Further controlled comparison studies have to be performed in the future.

Progress report on new antiepileptic drugs: a summary of the Seventh Eilat Conference (EILAT VII)

The Seventh Eilat Conference on New Antiepileptic Drugs (AEDs) (EILAT VII) took place in Villasimius, Sardinia, Italy from the 9th to 13th May 2004. Basic scientists, clinical pharmacologists and neurologists from 24 countries attended the conference,whose main themes included advances in pathophysiology of drug resistance, new AEDs in pediatric epilepsy syndromes, modes of AED action and spectrum of adverse effects and a re-appraisal of comparative responses to AED combinations. Consistent with previous formats of this conference, the central part of the conference was devoted to a review of AEDs in development, as well as updates on second-generation AEDs. This article summarizes the information presented on drugs in development, including atipamezole, BIA-2-093, fluorofelbamate, NPS 1776, pregabalin, retigabine, safinamide, SPM 927, stiripentol, talampanel,ucb 34714 and valrocemide (TV 1901). Updates on felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine,topiramate, vigabatrin, zonisamide, new oral and parenteral formulations of valproic acid and SPM 927 and the antiepileptic vagal stimulator device are also presented.

Acute management of seizures in the syndromes of idiopathic generalized epilepsies

Three of the seizure types (myoclonic, absence, and generalized tonic-clonic) and syndromes associated with idiopathic generalized or genetic epilepsies can present an acute status epilepticus picture that requires acute therapy. These are not the usual seizures observed in status epilepticus because most of these patients have secondary generalized or symptomatic generalized convulsive seizures. In this review, I discuss the unique presentation and treatment options for the acute management of seizures in the syndromes of idiopathic generalized epilepsy (IGE), with special emphasis on the seizures of status epilepticus, which persist over time or occur in a series without recovery of consciousness.

Safety and efficacy of intravenous valproate in pediatric status epilepticus and acute repetitive seizures

PURPOSE

To evaluate the safety and efficacy of intravenous valproate (VPA) loading in children with status epilepticus (SE) or acute repetitive seizures.

METHODS

Retrospective review was performed on 40 pediatric patients with intravenous VPA loading. Patients were classified into two groups: SE (n = 18) and acute repetitive seizures (n = 22). Thirty-one patients were VPA naïve and received a full loading dose of 25 mg/kg; nine had subtherapeutic plasma VPA levels and received a partial loading dose. Average infusion rate was 2.8 mg/kg/min. Heart rate and blood pressure were measured before, during, and after infusion.

RESULTS

Intravenous VPA loading stopped seizures in 18 patients with SE within 20 min. All 18 patients regained baseline mental status within 1 h of seizure cessation. Among 22 patients with acute repetitive seizures, only one had further seizures after VPA infusion. One patient in the SE group complained of transient tremors. No significant changes in blood pressure or heart rate were found in either group. Postinfusion plasma VPA levels ranged from 51 to 138 microg/ml (mean +/- SD = 88 +/- 21.5 microg/ml).

CONCLUSIONS

Intravenous VPA loading is safe and effective for treating acute seizure emergencies in children.

Valproate unbound fraction and distribution volume following rapid infusions in patients with epilepsy

The availability of an intravenous formulation now makes possible rapid administration of valproate (VPA) loading doses, but estimates of key VPA pharmacokinetic parameters in patients have limited the use of this approach. VPA disposition was characterized in 112 epilepsy patients, with or without enzyme inducing comedications, randomized to either 3.0 or 1.5mg/kg/min infusions of valproate sodium injection. Maximum dose was </=15mg/kg per infusion. Total and unbound plasma VPA concentrations were determined from blood samples obtained prior to and for 6h following the infusion. Analyses of covariance assessed the effect of induction, weight, age, gender, albumin, creatinine, and infusion rate on pharmacokinetics. Maximum total and unbound VPA concentrations were 94 and 14mg/l, respectively. Total concentration fell below 50mg/l within 3h in induced and 6h in uninduced patients. VPA unbound fraction decreased from 15% at maximum concentration to 9% at 45mg/l. The mean (S.D.) distribution volume was 0.21 (0.044)l/kg. Induction status, albumin concentration, and infusion rate significantly affected pharmacokinetics. Measurement of unbound VPA may be useful when alterations in binding are suspected. Infusions up to 3mg/kg/min produce predictable total VPA concentrations when induction status and albumin levels are considered.

Safety and tolerance of rapidly infused Depacon. A randomized trial in subjects with epilepsy

BACKGROUND

Valproate sodium injection (Depacon(R)) is an intravenous form of valproate for use in absence and complex partial seizures when circumstances preclude oral administration. Certain situations may warrant larger and more rapid infusions than permitted by the original labeling. This study evaluated the safety of more rapid infusions.

METHODS

Subjects with epilepsy were randomized in a 2:1 ratio to receive up to 15 mg/kg of valproate sodium infused at 3.0 or 1.5 mg/kg/min. Up to four infusions were allowed within 24 h to achieve target plasma valproate concentrations of 50-100 mcg/ml. Primary safety endpoints were the changes in the 5-min and minimum post-first infusion blood pressures (BPs).

RESULTS

One hundred twelve subjects were treated, (3.0 mg/kg/min group: n=72, 1.5 mg/kg/min group: n=40). No significant treatment differences were detected for changes in the primary BP endpoints. Two subjects in the 3.0 mg/kg/min group had potentially clinically significant low systolic BP values during the study. Similar proportions of subjects in the two groups reported adverse events during or within 6 h following the first infusion.

CONCLUSIONS

Valproate sodium injection dosages up to 15 mg/kg and rates of 1.5 and 3.0 mg/kg/min were well tolerated in this population.

The current state of treatment of status epilepticus

There have been many important developments in the diagnosis and treatment of status epilepticus in the recent past. Earlier treatment, including at home by caregivers and in the field by paramedics, has been shown to be safe and effective. Rapid-acting anesthetic agents, such as midazolam and propofol, are being used more often for refractory status epilepticus, though clinical trials are lacking. Nonconvulsive status epilepticus is being considered and recognized more often, including in ambulatory patients with a confusional state, after convulsive status epilepticus, and in critically ill patients. Modern technology and continuous digital electroencephalogram (EEG) recordings have taught us many things, but have raised at least as many questions. Much work needs to be done regarding the significance of certain EEG patterns (particularly periodic discharges) and when and how to treat them. This article reviews these issues, concentrating on recent advances and practical issues related to the clinical care of patients with status epilepticus.

Frontiers in Neuropharmacotherapy Part I: Alzheimer’s Disease and Epilepsy

Cholinesterase inhibitors, and particularly donepezil, are the standard of care in the management of Alzheimer’s disease. Newer agents, such as rivastigmine, galantamine, and metrifonate, provide therapeutic alternatives but have advantages and disadvantages compared with donepezil. Clinical studies and continued research of the pathophysiology of Alzheimer’s disease help define the role of both the newer agents and the original cholinesterase inhibitor, tacrine. Therapies with other mechanisms of action, such as estrogen and nonsteroidal anti-inflammatory drugs (NSAIDs), are also being actively investigated for their effects on cognition. Since 1993, 8 new antiepileptic drugs have been approved by the FDA, including felbamate, gabapentin, lamotrigine, topiramate, tiagabine, and 3 recently introduced agents, oxcarbazepine, levetiracetam, and zonisamide. These second-generation agents are generally more tolerable and have fewer drug interactions than traditional antiepileptics, and some provide alternative mechanisms that may be beneficial in the management of refractory epileptic disorders. However, until clinical experience with the newer antiepileptics accumulates and well-designed comparative trials are conducted, a review of individual studies of the safety and efficacy of the newer agents helps provide the basis for treatment decisions. New information regarding traditional therapies, including new formulations and updated treatment guidelines, also assist clinicians in optimizing antiepileptic therapy.

New antiepileptic drugs

BACKGROUND

Eight novel anticonvulsant drugs have been introduced in the United States in the past 10 years, as well as two new intravenous preparations of anticonvulsant drugs. The role of each in the treatment of patients with epilepsy is being refined as experience and research data accumulate.

REVIEW SUMMARY

Gabapentin, tiagabine, and oxcarbazepine are effective for partial seizures, whereas felbamate, lamotrigine, topiramate, levetiracetam, and zonisamide treat both partial and generalized seizure types. In general, these newer agents differ from older agents by relative lack of drug-drug interactions, and many show improved tolerability compared with phenytoin and carbamazepine. Each has distinguishing features that can prove useful in specific clinical situations. Despite limited Food and Drug Administration indications, all are useful in monotherapy under certain circumstances. Fosphenytoin avoids the adverse effects of intravenous phenytoin vehicle, and intravenous valproate represents a much needed option in patients who require rapid loading of this medication.

CONCLUSIONS

The greater number of antiseizure drugs available today makes it possible to tailor treatment to individual patient needs, allowing more patients to be free of debilitating adverse effects. Additionally, some patients can achieve complete seizure freedom even after failing one or more other antiepileptic drugs.

The acute effect of valproate on cerebral energy metabolism in mice

Sodium valproate (VPA) is used in the acute treatment of status epilepticus and mania. We studied the acute effect of VPA on cerebral energy metabolism in awake mice that received VPA 400 mg kg(-1) and [1-(13)C]glucose or [2-(13)C]acetate. At 25 min, (13)C NMR spectroscopy of brain extracts indicated inhibition of the tricarboxylic acid (TCA) cycle, as could be seen from the accumulation of [4-(13)C]glutamate and reduction in [(13)C]aspartate formation. Concomitantly, the level of ATP was reduced by 40%. To identify the enzymatic step at which the TCA cycle was inhibited [U-(14)C]alpha-ketoglutarate was injected intracerebrally. Inhibition of alpha-ketoglutarate dehydrogenase was evident at 25 min, as shown by accumulation of [(14)C]glutamate. At 45 min the inhibition of alpha-ketoglutarate dehydrogenase was reversed, shown by both (13)C- and (14)C-labeling, and the ATP level was normalized. The study shows for the first time that acute administration of VPA causes inhibition of the TCA cycle activity in vivo. The reduction in brain ATP would be expected to reduce neuronal excitability through modulation of sodium channels which may be clinically advantageous in the initial phase of VPA treatment.

Intravenous valproate in status epilepticus

OBJECTIVE

To evaluate the role of intravenous valproate sodium (IV VPA) in the treatment of status epilepticus (SE).

DATA SOURCES

A literature search of the English language was performed (MEDLINE 1966-July 2000). Search terms included valproate, valproic acid, and status epilepticus. Bibliographies of articles chosen were reviewed to identify other possible sources.

DATA SYNTHESIS

A review of the medical literature was conducted to evaluate the safety and efficacy of IV VPA in the treatment of SE.

CONCLUSIONS

Experience with IV VPA in the treatment of SE is too limited to recommend its use as a first-line agent. IV VPA may represent a third- or fourth-line option in cases of SE when other agents are ineffective or contraindicated.

Antiepileptic drugs in the 21st century

During the past 10 years, there has been a welcome influx of novel agents for the treatment of epilepsy. Many show advantages compared to older agents, including better adverse effect profiles and lack of drug-drug interactions. The sheer number of agents now available makes distinction among them confusing at times. Agents differ in spectrum of action, pharmacokinetic profile (affecting dosing schedule and drug interactions), and titration time. This review highlights the differences between the various new agents and the more traditional antiseizure drugs. Evidence for the widespread use of these compounds outside their indication, particularly for diseases other than epilepsy, is reviewed as well.

The role of intravenous valproic acid in status epilepticus

Valproic acid (VA) has been reported to be effective in status epilepticus (SE) when given rectally. More recently, intravenous (IV) VA has been demonstrated to be effective and safe. Pharmacokinetic studies and initial clinical experience with IV valproic acid suggest that it may have a useful role in the management of refractory status epilepticus, but the magnitude of its utility is not possible to quantify or compare with phenytoin and phenobarbital. In simple SE, IV VA provides less additional benefit, since standard therapy usually works well. IV VA may be useful as a substitute for standard simple SE therapy, but this is difficult to justify unless adverse reactions to standard therapy are anticipated. The published pediatric experience with IV VA for SE is scant.

Intravenous valproate in neuropsychiatry

Valproic acid (VPA) is administered for a variety of indications in neurology and psychiatry. The intravenous form of VPA, valproate, has been used extensively by neurologists since the 1980s for patients with status epilepticus, as serum levels can be achieved rapidly and telemetry is not required during administration. Psychiatrists have less experience with intravenous valproate, and little is documented in the literature regarding its nonepileptic indications. Patients who are unable or unwilling to take drugs orally, or for whom rapid treatment is clinically indicated, may benefit from VPA. Neuroleptics and benzodiazepines often are given parenterally; however, they may be accompanied by side effects. Intravenous valproate was administered successfully to three patients with neuropsychiatric disorders. It is hoped that this report will increase clinicians' awareness of this important and well-tolerated treatment option.

New formulations of drugs in epilepsy

The advent of numerous new treatment options in epilepsy therapy over the last decade is enabling a more flexible and individualized approach to patients with seizures. For some patients, these products offer added efficacy, reduction of troublesome side effects associated with standard anticonvulsants, and control over acute seizure exacerbations. This review profiles new formulations of anti-epileptic drugs. Tegretol-XR (TXR) and Carbatrol (CBTL), two extended-release preparations of carbamazepine (CBZ), which allow twice daily administration, minimising drug toxicity and improving efficacy. Topiramate sprinkles and lamotrigine chewable dispersible tablets allow easier administration in children. The rectal gel preparation of diazepam (Diastat) is useful for parents of patients with acute seizure exacerbations. Intravenous valproate (Depacon) and fosphenytoin (Cerebyx) provide parenteral treatment of acute seizures, without sedation or significant peripheral venous side effects. All of these new formulations expand treatment options for patients with epilepsy, who will benefit from them.