Behavioural effects of the new anticonvulsants

Efficacy and tolerability of levetiracetam in people with and without intellectual disabilities: A naturalistic case control study

INTRODUCTION

People with Intellectual Disabilities (PwID) are twenty times more likely than general population to have epilepsy. Guidance for prescribing antiseizure medication (ASM) to PwID is driven by trials excluding them. Levetiracetam (LEV) is a first-line ASM in the UK. Concerns exist regarding LEV's behavioural and psychological adverse effects, particularly in PwID. There is no high-quality evidence comparing effectiveness and adverse effects in PwID to those without, prescribed LEV.

METHODS

Pooled casenote data for patients prescribed LEV (2000-2020) at 18 UK NHS Trusts were analysed. Demographics, starting and maximum dose, adverse effects, dropouts and seizure frequency between ID (mild vs. moderate-profound (M/P)) and general population for a 12-month period were compared. Descriptive analysis, Mann-Whitney, Fisher's exact and logistic regression methods were employed.

RESULTS

173 PwID (mild 53 M/P 120) were compared to 200 without ID. Mean start and maximum dose were similar across all groups. PwID (Mild & M/P) were less likely to withdraw from treatment (P = 0.036). No difference was found between ID and non-ID or between ID groups (Mild vs M/P) in LEV's efficacy i.e. >50 % seizure reduction. Significant association emerged between ID severity and psychiatric adverse effects (P = 0.035). More irritability (14.2 %) and aggression (10.8 %) were reported in M/P PwID.

CONCLUSION

PwID and epilepsy have high rates of premature mortality, comorbidities, treatment resistance and polypharmacy but remain poorly researched for ASM use. This is the largest studied cohort of PwID trialled on LEV compared to general population controls. Findings support prescribing of LEV for PwID as a first-line ASM.

Gabapentin for Pain in Pediatric Palliative Care

OBJECTIVE

Gabapentin is commonly used to treat pain in children receiving pediatric palliative care. This study describes the real-world use of gabapentin and the associated benefits and adverse effects/events (AEs).

METHODS

A prospective, multicenter cohort of standardized data collection after a clinical decision was made to use gabapentin for managing neuropathic or nociplastic pain in children attended on by a pediatric palliative care service. It was conducted across 11 sites in seven countries including hospital, inpatient, and outpatient services. Clinical outcomes were graded using pain scales validated for age and cognitive ability and the National Cancer Institute Common Terminology Criteria for Adverse Events (NCICTCAE) at baseline, 14 days, 28 days, six weeks and 12 weeks after initiation of gabapentin. Ad-hoc safety reporting continued throughout the study.

RESULTS

Data were collected from 127 children with a median age of 4.7 years (IQR 0.1-17.9); 61% had a neurological disorder, 21% advanced cancer and the cohort had a high level of disability (Lansky/Karnofsky performance score 37.1). Gabapentin was prescribed at standard pediatric doses. On average, 76% of children had a reduction in pain and 42% experienced a potential AE. The mean pain score decreased from 6.0 (SD 2.6) at baseline to 3.3 (SD 2.4) at 14 days and 1.8 (SD 1.8) after 12-weeks of gabapentin therapy. Ten percent had increased pain at each time point. AEs did not increase when individual changes over time were accounted for except for somnolence (7%). Serious AEs attributable to gabapentin were possible or probable in 3% of children.

CONCLUSIONS

Gabapentin prescribed at standard doses for advanced cancer and severe neurological injury in children under a pediatric palliative care service was associated with generally improved pain intensity at previously described levels of adverse effects.

Pharmacotherapy compared to placebo for people with Bulimia Nervosa: A systematic review and meta-analysis

Bulimia Nervosa is a disorder with high rates of psychiatric and medical comorbidity and substantial societal costs. Cognitive Behavioural Therapy is considered the preferred treatment, but access can be problematic. Pharmacotherapy is more accessible but remains significantly underutilised. We aimed to assess the efficacy, tolerability, and safety of all available forms of pharmacotherapy for the treatment of bulimia nervosa. We conducted a comprehensive search of PubMed, EMBASE, CENTRAL, ClinicalTrials.gov, and reference lists of relevant articles up until April 2023. The primary outcomes were remission and binge frequency. 52 randomised controlled trials (RCTs) involving 3313 participants were included in the meta-analysis. Overall, no significant difference was observed between drugs and placebo in terms of remission; however, the available data were limited. Notably, drugs, particularly antidepressants, demonstrated a significant reduction in the frequency of binge episodes compared to placebo. Antidepressants were also found to be more effective than placebo in terms of treatment response and other clinically meaningful outcomes. An important limitation is that few RCTs were available for individual drugs. Our findings provide evidence supporting the increased utilisation of pharmacotherapy in clinical practice and underscore the need for further research involving larger populations and a broader range of outcomes.

Current and emerging pharmacotherapy for the treatment of Lennox-Gastaut syndrome

INTRODUCTION

Lennox-Gastaut syndrome (LGS) is a severe childhood-onset epileptic encephalopathy, characterized by multiple seizure types, generalized slow spike-and-wave complexes in the EEG, and cognitive impairment. Seizures in LGS are typically resistant to treatment with antiseizure medications (ASMs). Tonic/atonic ('drop') seizures are of particular concern, due to their liability to cause physical injury.

AREAS COVERED

We summarize evidence for current and emerging ASMs for the treatment of seizures in LGS. The review focuses on findings from randomized, double-blind, placebo-controlled trials (RDBCTs). For ASMs for which no double-blind trials were identified, lower quality evidence was considered. Novel pharmacological agents currently undergoing investigation for the treatment of LGS are also briefly discussed.

EXPERT OPINION

Evidence from RDBCTs supports the use of cannabidiol, clobazam, felbamate, fenfluramine, lamotrigine, rufinamide, and topiramate as adjunct treatments for drop seizures. Percentage decreases in drop seizure frequency ranged from 68.3% with high-dose clobazam to 14.8% with topiramate. Valproate continues to be considered the first-line treatment, despite the absence of RDBCTs specifically in LGS. Most individuals with LGS will require treatment with multiple ASMs. Treatment decisions should be individualized and take into account adverse effects, comorbidities, general quality of life, and drug interactions, as well as individual efficacy.

Systematical exploration of the common solvent toxicity at whole organism level by behavioral phenomics in adult zebrafish

Common solvents are frequently used as carriers to dissolve chemicals with a hydrophobic property that is extensively applied in the industrial and biomedical fields. In this study, we aimed to systematically study the sub-chronic effect of ten common solvents at low concentration exposure in adult zebrafish and perform neurobehavioral assessments for mechanistic exploration. After exposed to ten common solvents, including methanol, ethanol (EtOH), dimethyl sulfoxide (DMSO), isopropanol, acetone, polyethylene glycol-400 (PEG-400), glycerol, butanol, pentane, and tetrahydrofuran for continuous 10 day at 0.1% concentration level, adult zebrafish were subjected to perform a serial of behavioral tests, such as novel tank, mirror biting, predator avoidance, social interaction and shoaling. Later, 20 behavioral endpoints obtained from these five tests were transformed into a scoring matrix. Principal component analysis (PCA) and hierarchy clustering were performed to evaluate and compare the zebrafish behavior profiling. By using this phenomic approach, we were able to systematically evaluate the toxicity of the common solvents in zebrafish at a neurobehavioral level for the first time and found each common solvent-induced unique behavioral alteration to produce fingerprint-like patterns in hierarchy clustering and heatmap analysis. Among all tested common solvents, acetone and PEG-400 displayed better biocompatibility and less toxicity since they triggered less behavioral and biochemical alterations while methanol and DMSO caused severe behavior alterations in zebrafish after chronic exposure of these solvents. We conclude the behavioral phenomic approach conducted in this study providing a powerful tool to a systematical exploration of the common solvent toxicity at the whole organism level.

Network meta-analysis of antiepileptic drugs in focal drug-resistant epilepsy

OBJECTIVE

To compare and rank the efficacy and acceptability of new antiepileptic drugs (AEDs) for patients with focal drug-resistant epilepsy.

METHODS

PubMed, EMBASE, Cochrane databases and Clinicaltrials.gov were systematically searched from their inception through January 1, 2020, to identify trials evaluating AEDs for focal drug-resistant epilepsy. We included randomized controlled clinical trials (RCTs) comparing new AEDs with placebo or with other AEDs as adjunctive therapy for focal drug-resistant epilepsy. A Bayesian network meta-analysis was performed to determine efficacy and acceptability, as reflected by odds ratios (ORs), 95 % credible intervals (CrIs) with random-effects and consistent models.

RESULTS

Sixty-two RCTs were included, involving 12,739 patients with focal drug-resistant epilepsy. Regarding the seizure-free rate (40 RCTs involving 9,136 patients), 8 AEDs were more efficacious than placebo, with lnORs ranging between 1.69 for brivaracetam (95 % CrI, 0.56-2.81) and 0.72 for pregabalin (95 % CrI, 0.12-1.32). Regarding the responder rate, all AEDs except oxcarbazepine were more efficacious than placebo, with lnORs ranging between 1.31 for levetiracetam (95 % CrI, 0.92-1.71) and 0.66 for carisbamate (95 % CrI, 0.17-1.14). Regarding acceptability (60 RCTs comprising 12,139 patients), 9 AEDs were inferior to placebo. Estimated from seizure-free rate, brivaracetam was ranked as the most efficacious AED based on cumulative probability plots and SUCRAs, with fatigue as the main adverse event.

CONCLUSION

The results indicate that, based on seizure-free rate and all-cause discontinuation rate, brivaracetam is the most efficacious and acceptable AED, with mild adverse events and acknowledgement of potential publication bias.

Psychiatric side-effects of medications: recent developments

Medications often induce neuropsychiatric side-effects. This article reviews psychiatric side-effects that are well known and describes those induced by recently developed medications. Therapeutic innovations have been prominent in the treatment of HIV infection, Parkinson's disease and epilepsy and therefore psychiatric side-effects caused by these agents are described in more detail.

Chromatographic determination of zonisamide, topiramate and sulpiride in plasma by a fluorescent 'turn-on' chemosensor

AIM

Antiepileptics (AEDs) and antipsychotics are often coprescribed. Interactions between these drugs may affect both efficacy and toxicity. Therefore, drug monitoring is necessary for appropriate dosage adjustments.

MATERIALS & METHODS

Specific 'turn-on' chemosensor, 4-chloro-7-nitrobenzofurazan is used for selective and sensitive determination of two AEDs: zonisamide (ZON) and topiramate (TOP) with the antipsychotic sulpiride (SUL) in epileptic patients' plasma followed by reversed-phase-HPLC separation without any interference.

RESULTS

Linear behavior was observed in the range of 0.1-3 μg/ml and 0.01-0.5 μg/ml for the AEDs and SUL, respectively, with LOD of 33, 46 and 4 ng/ml and LOQ of 86, 93 and 9 ng/ml for ZON, TOP and SUL, respectively. The proposed method was successfully applied for determination of different pharmacokinetic parameters of ZON and TOP, and for clinical monitoring of the three drugs in healthy volunteers following oral administration.

CONCLUSION

The developed method is suitable for the routine therapeutic drug monitoring of these drugs.

Medicinal-Induced Behavior Disorders

Commonly used medications can have neuropsychiatric and behavioral effects that may be idiosyncratic or metabolic in nature, or a function of interactions with other drugs, toxicity, or withdrawal. This article explores an approach to the patient with central nervous system toxicity, depending on presentation of sedation versus agitation and accompanying physical signs and symptoms. The effects of antihypertensives, opioids, antibiotics, antiepileptic agents, steroids, Parkinson's disease medications, antipsychotics, medications for human immunodeficiency virus infection, cancer chemotherapeutics, and immunotherapies are discussed. A look at the prevalence of adverse reactions to medications and the errors underlying such occurrences is included.

Epilepsy, Antiepileptic Drugs, and Aggression: An Evidence-Based Review

Antiepileptic drugs (AEDs) have many benefits but also many side effects, including aggression, agitation, and irritability, in some patients with epilepsy. This article offers a comprehensive summary of current understanding of aggressive behaviors in patients with epilepsy, including an evidence-based review of aggression during AED treatment. Aggression is seen in a minority of people with epilepsy. It is rarely seizure related but is interictal, sometimes occurring as part of complex psychiatric and behavioral comorbidities, and it is sometimes associated with AED treatment. We review the common neurotransmitter systems and brain regions implicated in both epilepsy and aggression, including the GABA, glutamate, serotonin, dopamine, and noradrenaline systems and the hippocampus, amygdala, prefrontal cortex, anterior cingulate cortex, and temporal lobes. Few controlled clinical studies have used behavioral measures to specifically examine aggression with AEDs, and most evidence comes from adverse event reporting from clinical and observational studies. A systematic approach was used to identify relevant publications, and we present a comprehensive, evidence-based summary of available data surrounding aggression-related behaviors with each of the currently available AEDs in both adults and in children/adolescents with epilepsy. A psychiatric history and history of a propensity toward aggression/anger should routinely be sought from patients, family members, and carers; its presence does not preclude the use of any specific AEDs, but those most likely to be implicated in these behaviors should be used with caution in such cases.

Pharmacological interventions for epilepsy in people with intellectual disabilities

BACKGROUND

The prevalence of epilepsy among people with intellectual disabilities is much higher than in the general population. Seizures in this population are often complex and refractory to treatment and antiepileptic medication may have a profound effect upon behaviour (Kerr 1997).This is an updated version of a Cochrane Review first published in Issue 3, 2007.

OBJECTIVES

To assess the data available from randomised controlled trials (RCTs) of the efficacy of antiepileptic drug (AED) interventions in people with epilepsy and intellectual disabilities.

SEARCH METHODS

For the latest update of this review, we searched the Cochrane Epilepsy Group Specialised Register (2 September 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO) (2 September 2014), MEDLINE (Ovid, 1946 to 3 September 2014) and PsycINFO (EBSCOhost, 1887 to 3 September 2014).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials (RCTs) of pharmacological interventions for people with epilepsy and a learning disability.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We assessed epilepsy/seizure, behavioural and cognitive outcomes, as well as quality of life and adverse effects.

MAIN RESULTS

We included 14 RCTs (1116 participants) in the present review. Data were heterogenous and a descriptive analysis is presented. In the majority of cases where antiepileptic drugs (AEDs) were trialled in this population, we found moderate reductions in seizure frequency in that there was a significantly higher rate of responders (reduction of 50% or more) in the treatment group compared with the placebo group, with some studies reporting a higher incidence of seizure freedom in the treatment group. In general, AEDs that are proven to be effective in the general epilepsy population are also effective for refractory epilepsy in people with intellectual disability. It is not possible to comment on the relative efficacy of medications, making clinical decisions difficult.In trial settings patients continued on treatment in the majority of cases. Placebo groups often experienced fewer adverse events. Where adverse events were experienced they appeared similar to those in the general population. The methods by which adverse events were recorded and reported appeared to be inconsistent, resulting in very large variation between studies. This is problematic as clinically relevant interpretation of these findings is limited.The quality of evidence provided in the present review is low to moderate. Additionally the majority of studies lacked or used non-reliable measures of behavioural exacerbation. However, where measured, little obvious impact on behaviour was seen in terms of behaviour disorder.

AUTHORS' CONCLUSIONS

This review broadly supports the use of AEDs to reduce seizure frequency in people with refractory epilepsy and intellectual disability. The evidence suggests that adverse events are similar to those in the general population and that behavioural adverse events leading to discontinuation are rare; however, other adverse effects are under-researched.

Behavioral impairments in rats with chronic epilepsy suggest comorbidity between epilepsy and attention deficit/hyperactivity disorder

Attention deficit/hyperactivity disorder (ADHD) is encountered among patients with epilepsy at a significantly higher rate than in the general population. Mechanisms of epilepsy-ADHD comorbidity remain largely unknown. We investigated whether a model of chronic epilepsy in rats produces signs of ADHD, and thus, whether it can be used for studying mechanisms of this comorbidity. Epilepsy was induced in male Wistar rats via pilocarpine status epilepticus. Half of the animals exhibited chronic ADHD-like abnormalities, particularly increased impulsivity and diminished attention in the lateralized reaction-time task. These impairments correlated with the suppressed noradrenergic transmission in locus coeruleus outputs. The other half of animals exhibited depressive behavior in the forced swimming test congruently with the diminished serotonergic transmission in raphe nucleus outputs. Attention deficit/hyperactivity disorder and depressive behavior appeared mutually exclusive. Therefore, the pilocarpine model of epilepsy affords a system for reproducing and studying mechanisms of comorbidity between epilepsy and both ADHD and/or depression.

Problematic behavior in children with epilepsy: issues and management

This chapter is written on the premise the neurologist who will take on a new case of epilepsy or will have behavioral problems arise in an old case. "behavioral problems" is preferred to "psychiatric disorders" because the behavior is described by the parents and can be evident to the neurologist. All "behavior" is organized in the brain and can be dysfunctional if cerebral function is impaired by lesions, by genetic aberrations, or by medications. Epilepsy is also liable to give rise to prejudicial responses in all concerned. A detailed history of the family unit is essential from the start. The "illness" of epilepsy will arise from structural "disease" and will give rise to a painful "predicament"; anguish, distress. And all this is in a particular context. The best possible solution for the child will have to be "negotiated," rather than prescribed. Psychopathology also arises from "everyday life"; from the fact of chronic illness; and from alienation. These aspects are explored in detail. Mental handicap, specific learning difficulties, ADHD, and autism are frequently specifically associated with epilepsy.

Beneficial and adverse psychotropic effects of antiepileptic drugs in patients with epilepsy: a summary of prevalence, underlying mechanisms and data limitations

Antiepileptic drugs (AEDs) can have both beneficial and adverse psychotropic effects. They act on neurotransmitter systems, neuronal ion permeability and other targets, although the exact mechanisms are not generally fully elucidated. A systematic review of the literature reveals evidence for both positive and negative effects on depression, anxiety, aggression, psychosis and sleep in patients with epilepsy. Topiramate, vigabatrin, levetiracetam, tiagabine and zonisamide have been associated primarily with adverse psychotropic effects, whilst gabapentin, pregabalin, lacosamide and lamotrigine, in particular, have demonstrated a more beneficial psychotropic profile, especially with regard to affective symptoms. This review, however, identifies specific methodological issues with studies that have reported on the psychotropic effects of AEDs, suggesting that some of the findings might be inconclusive or unreliable because of confounding factors, particularly the presence of psychiatric history. More rigorous double-blind, randomized, placebo-controlled trials on larger numbers of patients with epilepsy, with clear inclusion/exclusion criteria, that are specifically designed to investigate psychotropic changes are more likely to produce results that inform clinical practice and direct future research.

New developments in the treatment of partial-onset epilepsy

Although most people presenting with partial-onset seizures will achieve control with antiepileptic medication, a considerable minority will have difficult-to-treat epilepsy that is resistant to existing medication. Over the last few years, a large number of new antiepileptic drugs have been developed. Some of these have a novel mode of action. Many of the older antiepileptic drugs act through sodium channels or by enhancement of gamma amino butyric acid (GABA). Lamotrigine has sodium-channel blocking properties but also has other important modes of action, indicated by efficacy in treating not only partial-onset but also generalized seizures. Vigabatrin and tiagabine both increase GABA activity, by inhibiting GABA transaminase and limiting GABA reuptake, respectively. The main mode of action of gabapentin and pregabalin is not via GABA but through a selective inhibitory effect on voltage-gated calcium channels containing the α(2)δ-1 subunit. Levetiracetam inhibits the recycling of SV2A (synaptic vesicle protein 2A) neurotransmitter vesicles but also has other effects, including inhibition of voltage-dependent calcium channels. Some drugs, eg, felbamate, zonisamide, and topiramate, have multiple modes of action. In many cases, although the main mode of action may have been identified, other modes of action also play a role. Two recently developed antiepileptic drugs appear to have completely novel primary modes of action; retigabine (ezogabine) and perampanel act on the potassium channel and on AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors, respectively. The hope is that antiepileptic drugs with a novel mode of action will be effective where previous drugs have failed and will not have unacceptable adverse effects. However, experience with these medications is too limited to allow any conclusions to be drawn at present.

Zonisamide discontinuation due to psychiatric and cognitive adverse events: a case-control study

OBJECTIVES

Zonisamide (ZNS) is an antiepileptic drug (AED) that has been associated with psychiatric adverse events (PAE) and cognitive adverse events (CAE); controlled studies evaluating these adverse events are limited. Our objectives were to 1) determine the incidence of PAE and CAE leading to the discontinuation of ZNS and 2) identify risk factors for PAE and CAE associated with the discontinuation of ZNS.

METHODS

All patients exposed to ZNS at MINCEP Epilepsy Care between March 2000 and September 2008 were identified. Reasons for discontinuing ZNS were documented. Separate case-control studies were performed to identify risk factors associated with the discontinuation of ZNS due to PAE or CAE via multivariate binary logistic regression.

RESULTS

A total of 544 patients were exposed to ZNS during the study period. PAE and CAE were the most frequently identified reasons for terminating ZNS therapy. The incidence of PAE severe enough to be associated with the discontinuation of ZNS was 6.9%; the incidence of CAE was 5.8%. Factors associated with termination of ZNS therapy due to PAE were past psychiatric history (p = 0.005), symptomatic generalized epilepsy (p = 0.027), and lower maximum ZNS serum concentration (mean = 17.9 mg/L vs 34.7 mg/L, p < 0.001). Independent variables associated with discontinuing ZNS due to CAE were greater number of concomitant AEDs (p = 0.011) and lower maximum ZNS serum concentration (mean = 16.6 mg/L vs 30.6 mg/L, p = 0.002).

CONCLUSIONS

We have identified clinically relevant risk factors associated with the discontinuation of ZNS. Our findings support the concept that selected patients are relatively more vulnerable to CNS adverse events when exposed to ZNS.

Psychotropic effects of antiepileptic drugs

Antiepileptic drugs are important psychotropic agents that are commonly used to treat psychiatric disorders. The behavioral effects of antiepileptic drugs may differ between epilepsy and psychiatric patient populations. Randomized, double-blind, controlled data on the psychotropic efficacy of antiepileptic drugs are limited mainly to bipolar disorder.

Review of topiramate for the treatment of epilepsy in elderly patients

Individuals over 65 years of age experience the new onset of seizures at a prevalence rate of roughly twice that of younger adults. Differences in physiology, need of concomitant medications, and liability for cognitive deficits in this population, make the choice of anticonvulsant drugs especially important. This paper reviews topiramate (TPM), a treatment for many types of seizures, with the above risks in mind. In particular, we discuss efficacy and pharmacokinetics with emphasis on the older patient, and adverse events in both the younger and older adult. With most studies of TPM-induced cognitive deficits having been performed in younger adults and volunteers, we discuss the implications for the older adult. Even in studies of younger individuals, up to 50% discontinue TPM because of intolerable cognitive deficits. Most studies find specific declines in working memory and verbal fluency. In conclusion, we give recommendations for use of this antiepileptic drug in this population.

Association between attention-deficit/hyperactivity disorder and epilepsy in pediatric populations

There is a bidirectional relationship between attention-deficit/hyperactivity disorder (ADHD) and epilepsy. ADHD increases seizure risk, while patients with epilepsy have an increased prevalence of ADHD. The reasons explaining this association are not fully understood. Proposed mechanisms include effects of antiepileptic medications, underlying neurodevelopmental vulnerability, the effects of chronic seizures and subclinical epileptiform activity on cognitive functions and adrenergic dysfunction. There may also be a common genetic defect underlying both disorders in some families. Antiepileptics associated with ADHD-like side effects include phenobarbital, gabapentin, vigabatrin and topiramate. Methylphenidate has been studied in a double-blind setting against placebo for treatment of ADHD comorbid with epilepsy, and has a good risk-benefit ratio. Amphetamine, atomoxetine, clonidine and guanfacine only have case series to support their use and bupropion should be avoided.

The role of titration schedule of topiramate for the development of depression in patients with epilepsy

PURPOSE

To determine whether a fast titration schedule of topiramate (TPM) has different effects on the occurrence of depression, in relation to other risk factors for TPM-induced depression, including history of depression (HxDEP), febrile seizures (FS), and hippocampal sclerosis (HS).

METHODS

Using data from a large case registry of patients prescribed TPM, two models were constructed: Model 1 examined the independent effect of rapid TPM titration after separate adjustment for FS, HxDEP, and HS. Model 2 examined effect of the cooccurrence of rapid titration on the development of depression with each of these risk factors.

RESULTS

A total of 423 patients were included (51.8% females), mean age (SD) 35.5 (11.8) years, mean duration of epilepsy of 22.2 (11.5) years. Forty-four patients (10.4%) developed depression during TPM therapy. A rapid TPM titration was associated with 5-fold increased risk of depression that increased to 12.7-fold in the presence of both FS and rapid TPM titration, 23.3-fold in the presence of both HxDEP and rapid TPM titration, and 7.6-fold in the presence of both HS and rapid TPM titration schedule.

CONCLUSIONS

Our study suggests that a rapid titration schedule is associated with an increased risk of developing depression during TPM therapy. HxDEP and FS are major contraindications to the use of a rapid titration, with a 23.3-fold and 12.7 fold increased risk, respectively.

Depression and mental health help-seeking behaviors in a predominantly African American population of children and adolescents with epilepsy

PURPOSE

To determine whether previously undetected symptoms of depression and psychiatric help-seeking behaviors are associated with demographic or epilepsy-related variables in a predominantly African American sample of pediatric epilepsy patients.

METHODS

Ninety-six serially recruited parent-child dyads (55% African American, 39% Caucasian) completed the Short Mood and Feelings Questionnaire (SMFQ). Regression analyses determined whether depressive symptoms measured by the SMFQ were associated with demographic (age, gender, and ethnic background) or epilepsy-related variables (age of seizure onset, duration of epilepsy, seizure type, time since last seizure, and number of antiepileptic drugs). Dyads with positive SMFQ screens (score > or = 12) received information about depression and were advised to seek mental health services. Six months later, parents completed follow-up interviews to ascertain mental health service utilization.

RESULTS

Thirty-five participants (36.5%) screened positive for probable depression. Greater number of antiepileptic drugs was the only predictor variable independently associated with greater (worse) depression scores (p = 0.005). At 6-month follow-up, 12 patients (36.4%) had received mental health care, whereas 21 guardians (63.6%) denied depressive symptoms in their child and never sought mental health services (two dyads lost to follow-up). Logistic regression analyses found no associations between demographic, epilepsy-related, or depressive variables and psychiatric help-seeking.

DISCUSSION

This study indicates the necessity and feasibility of screening for previously undetected symptoms of depression in pediatric epilepsy clinics serving diverse populations, particularly among patients receiving antiepileptic polytherapy. Additional research on the correlates of depressive symptoms and determinants of psychiatric help-seeking is needed to develop evidence-based interventions for youths with epilepsy and symptoms of depression.

Topiramate: a review of its use in the treatment of epilepsy

Topiramate (Topamax) is a structurally novel broad-spectrum antiepileptic drug (AED) with established efficacy as monotherapy or adjunctive therapy in the treatment of adult and paediatric patients with generalised tonic-clonic seizures, partial seizures with or without generalised seizures, and seizures associated with Lennox-Gastaut syndrome. The incidence and severity of many adverse events, including CNS-related events, may be reduced through the use of slow titration to effective and well tolerated dosages. It is associated with few clinically significant interactions with other drugs, is effective when used with other AEDs, is not associated with drug-induced weight gain and, at lower dosages, does not interfere with the effectiveness of oral contraceptives. Therefore, topiramate is a valuable option as monotherapy or adjunctive therapy in the treatment of epilepsy in adult and paediatric patients.

Role of GABA in anxiety and depression

This review assesses the parallel data on the role of gamma-aminobutyric acid (GABA) in depression and anxiety. We review historical and new data from both animal and human experimentation which have helped define the key role for this transmitter in both these mental pathologies. By exploring the overlap in these conditions in terms of GABAergic neurochemistry, neurogenetics, brain circuitry, and pharmacology, we develop a theory that the two conditions are intrinsically interrelated. The role of GABAergic agents in demonstrating this interrelationship and in pointing the way to future research is discussed.

Interactions between seizure frequency, psychopathology, and severity of intellectual disability in a population with epilepsy and a learning disability

Despite observations associating lower IQ and psychopathology in epilepsy, the possible differential effects of varying severity of learning (intellectual) disability (LD) on the manifestation of psychopathology in people with LD and epilepsy have not been clarified. In this study of retrospectively collected data describing the epilepsy, learning disability, and psychopathology of 175 patients with epilepsy and LD over a 3-month period, we observed that 65 patients had no recent seizures, whereas 110 had experienced at least one seizure in the preceding 3 months. We found that depression and psychoses were more common in those with no seizures in the preceding 3 months, but that which of these psychiatric states was manifest was related to the severity of LD. Psychosis rates were higher in those with mild LD, whereas depression rates were higher in those with severe LD.

Pharmacological interventions for epilepsy in people with intellectual disabilities

BACKGROUND

The development of epilepsy in a person with intellectual disabilities is a common occurrence. In view of the fact that seizures in intellectually disabled people are often complex and refractory to treatment and that antiepileptic medication may have a profound effect upon behaviour in this patient group, it is evident that good quality randomised controlled trials are needed in this population.

OBJECTIVES

The aim of our study was to assess the data available from randomised controlled trials of antiepileptic drug interventions in people with epilepsy and intellectual disabilities.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2006, Issue 4), MEDLINE OVID (1966 to October 2006), PsychInfo OVID (1806 to October 2006) and EMBASE OVID (1980 to April 2005).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of pharmacological interventions for people with epilepsy and a learning disability. RCTs where inadequate methods of allocation concealment had been used were also included.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. Outcome measures included the following.(1) Retention on treatment.(2) Seizure freedom.(3) Reduction in seizure frequency.(4) Seizure severity scales.(5) Global rating scales.(6) Behavioural outcomes.(7) Cognitive outcomes.(8) Adverse effects.(9) Quality of life.

MAIN RESULTS

Data were heterogenous and a descriptive analysis is presented. This review confirms that in the majority of cases where antiepileptic drugs (AEDs) were trialled in this population, moderate reduction in seizure frequency and occasional seizure freedom were obtained. In general it seems reasonable to say that AEDs proven effective in the general epilepsy population are also effective in refractory epilepsy in people with intellectual disability. It is not possible to comment on relative efficacy between medications making clinical choice decisions difficult. Clinical decision is also likely to be guided by concern over side effects. The quality of the studies does not aid clinicians greatly to this respect. In general it seems that in trial settings patients continue on treatment, in the majority of cases, and placebo groups often experience less in the way of side effects. Where side effects are experienced they appear similar to those seen in non-intellectual disability studies. One area of key concern is that of behavioural exacerbation. The majority of studies are unhelpful due to lack of or non-reliable measures in this area. However, where measured, little obvious impact on behaviour is seen in terms of behaviour disorder.

AUTHORS' CONCLUSIONS

In summary this review broadly supports the use of AEDs to reduce seizure frequency in people with refractory epilepsy and intellectual disability. The evidence suggests that side effects are similar to those in the general population and that behavioural side effects leading to discontinuation are rare but that other effects are under researched.

Critical care sedation for neuroscience patients

In 2000, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) introduced the mandate for the implementation of standards for both pain assessment and need for therapy in hospitalized patients. The need for the appropriate titration of sedation and analgesia is particularly poignant in an intensive care unit (ICU) setting where iatrogenic discomfort often complicates patient management. Neurologically ill patients in ICUs present particularly complex sedation issues, owing to the need to monitor these patients with serial neurological exams. Hence, maximal comfort without diminishing neurological responsiveness is desirable. Here, we review the frequently applied methods of evaluating levels of pain and agitation in critically ill patients as well as discuss the appropriate classes of pharmaceutical agents common to this population, with particular emphasis on the potential neurophysiological impact of such therapy.

Retention rate of levetiracetam in children with intractable epilepsy at 1 year

Levetiracetam (LEV) is a novel antiepileptic drug (AED) that has recently obtained marketing authorisation for use in children. The purpose of this study was to assess the efficacy, tolerability and retention rate of LEV in children with refractory epilepsies. It is a retrospective multicentre observational study reporting the use of LEV in 200 children, aged 0.3-19 years (median 9-years-old) over a 4-year period. All of the patients included in the study had refractory epilepsy with a median age of onset of epilepsy of 3 years (range 0-13 years). The 38% had failed and withdrawn 3 or more AEDs previously and 24% were taking at least 2 other AEDs in addition to LEV. The 47% had focal, and 58% had symptomatic epilepsies. The LEV dose ranged from 8 to 100 mg/kg/day (mean 39 mg/kg). The study comprised 215 person years of LEV exposure.

RESULTS

LEV was well tolerated with a retention rate of 49% at 1 year. No serious adverse events were reported with possibly related adverse events reported in only 24% of patients (mainly emotional or behavioural changes). At more than 2, 6 and 12 months, worthwhile improvement (>50% seizure reduction) was noted in 60, 40 and 32%, including seizure freedom in 14, 14 and 5%, respectively.

CONCLUSION

Our results confirm the efficacy and tolerability of LEV in children with refractory epilepsies and demonstrate good response and retention rates at 12 months. It represents the largest cohort of paediatric patients published so far on LEV with a 1-year follow-up.

Suicidality and Antiepileptic Drugs

The main purpose of the present article is to review the possible risk factors for suicidal behaviour in epilepsy with a special emphasis on the different antiepileptic drugs (AEDs). Epidemiological data show that, in general, the suicide rate among patients with epilepsy is 5-fold higher than that in the general population, while in temporal lobe epilepsy and complex partial seizures it is approximately 25-fold higher. A certain psychiatric comorbidity may provoke suicidality in patients with epilepsy, and depression and cognitive impairment seem to be the main risk factors for suicidality in epilepsy. In addition, depression and cognitive deterioration in epilepsy may share common neuropsychological mechanisms in terms of hypofrontality. This may cause similar psychopathological signs in both diagnostic categories, including suicidality. Analysis of the literature has shown that serotonin metabolism disturbances are involved in the pathogenesis of suicidal behaviour irrespective of primary diagnosis. Serotonin disturbances also seem to be a common link between depression, suicidality and even epilepsy itself. The various AEDs differ not only in their mechanisms of action, but also in influences on cognition and mood in epileptic patients and suicidality, respectively. Until now, only Ketter's hypothesis has been proposed to explain the psychotropic effects of different AEDs, although it does not explain the positive psychotropic effects of some AEDs, such as carbamazepine and oxcarbazepine. According to this model, all psychotropic effects of AEDs may be the result of effects on the function of two types of receptor functions: gamma-aminobutyric acid (GABA) ergic and antiglutamatergic; other possible mechanisms have not been incorporated. Presumably, other neurochemical mechanisms, and a serotonergic mechanism in particular, should also be taken into account when explaining the psychotropic effects of different AEDs. Based on these data, it has been suggested that AEDs with certain serotonergic properties should reduce the suicidality risk because they exert effects similar to antidepressants (i.e. selective serotonin reuptake inhibitors), whereas AEDs that lack serotonergic mechanisms would not be effective in suicidality prevention. In line with this paradigm, phenobarbital and phenytoin seem to be the only drugs with proven suicidality risk. On the other hand, carbamazepine, oxcarbazepine, valproate and lamotrigine could be regarded as drugs with antisuicidal properties because they all improve cognitive functions and mood in epileptic patients, and possess serotonergic mechanisms of action. The other AEDs, including topiramate, tiagabine, vigabatrin, levetiracetam and zonisamide, all exert negative effects on mood and cognition, although their influence on suicidality has not been proven in evidence-based studies yet. Although zonizamide has serotonergic properties, it exerts negative psychotropic effects, whereas gabapentin is devoid of serotonergic properties but has positive psychotropic effects on mood and cognition. To more fully explain the positive and negative psychotropic effects and influence on suicidality of AEDs, Ketter's paradigm should be supplemented by an understanding of the serotonergic mechanisms of different AEDs. Further trials are required to prove or refute this model.

Effects of Antiepileptic Drugs on Mood and Behavior

Psychiatric disorders in epilepsy have a multifactorial etiology, pharmacotherapy being only one of many risk factors, which can be both biological and psychosocial. Two important mechanisms of drug-induced psychiatric changes are seizure control/forced normalization in psychosis and GABA-ergic effects in depression. Among the psychiatric adverse events of antiepileptic drugs (AEDs), behavioral problems are the most commonly reported, followed by affective disorders. Psychosis is a relatively rare, although severe, complication. Psychotropic effects of AEDs warrant further research because many relevant parameters related to pathological mechanisms, frequency, psychopathology, and prognosis are not well understood. Behavioral side-effect profiles of AEDs, both negative and positive psychotropic effects, should be considered in the choice of the optimal drug for an individual patient.

Cognitive and Behavioral Outcomes of Epileptic Syndromes: Implications for Education and Clinical Practice

The educational and social progress of a child with epilepsy depends not only on seizure control but also on cognitive and behavioral factors. The various epilepsy syndromes of childhood and adolescence differ greatly in terms of cognitive and behavioral outcome. A high proportion of babies who have West syndrome and children who have Dravet syndrome (severe myoclonic epilepsy in infancy) will have long-term cognitive and behavioral problems. The Lennox-Gastaut syndrome also often has a poor prognosis in this regard. Children with the Landau-Kleffner syndrome have a variable prognosis, some regain speech and others have permanent speech impairment. Benign childhood epilepsy with centrotemporal spikes is now recognised as lying on a spectrum with the Landau-Kleffner syndrome: mild cases have few if any cognitive or behavioral problems but others may have quite severe difficulties. People with juvenile myoclonic epilepsy may have characteristics suggesting frontal lobe impairment. The educational and social impairments associated with the epilepsy syndromes of childhood and adolescence are of major importance but they have been the subject of remarkably few well-performed studies. The impairments are not always necessarily permanent and it seems highly likely that the cognitive and behavioural outcome of at least some of these syndromes can be influenced greatly by early effective treatment with either antiepileptic medication or surgery.

Role of valproate across the ages. Treatment of epilepsy in adults

A workshop was held in Göteborg in June 2005 to discuss the place of valproate in treating adult epilepsies. Consensus positions were developed on the epilepsy types for which the drug is most suitable and the use of valproate in women of child-bearing age, in men and in patients with psychiatric comorbidity. Valproate was considered to be effective across a broad variety of epilepsy syndromes and seizure types and should be considered a suitable choice for first-line monotherapy of juvenile myoclonic epilepsy and other idiopathic generalized epilepsies. The use of valproate by women of child-bearing age is associated with potential harm to the foetus. A conservative approach to treatment is recommended in these patients whereby alternative antiepileptic drugs should be proposed to women planning pregnancies wherever satisfactory seizure control can be thereby maintained. In cases where valproate is used during pregnancy, either because the pregnancy was unplanned or because alternative treatment options of equivalent efficacy are unavailable, appropriate counselling, precautionary measures and monitoring should be provided. The evidence for an impact of valproate on male reproductive health is equivocal and considerations of male fertility should not be taken into account in deciding whether to prescribe valproate to men. Valproate can be proposed safely to patients with comorbid psychiatric disease or underlying psychiatric vulnerability.

Clinical experience with anticonvulsant medication in pediatric epilepsy and comorbid bipolar spectrum disorder

Anticonvulsant drugs are first-line treatments for both bipolar mood disorder and epilepsy; however, few studies have explored treatment options when these disorders co-occur. The aim of this study was to identify bipolar disorder symptoms common in pediatric epilepsy and to determine whether anticonvulsant monotherapy might be a practical treatment consideration. A retrospective chart review identified 38 children with bipolar spectrum disorder and epilepsy comorbidity. Two mental health clinicians independently assessed psychiatric diagnoses, symptoms, and assigned retrospective CGI-I ratings for psychiatric symptoms. Common bipolar symptoms included impulsivity, psychomotor agitation, and explosive rage. Forty-two medication trials with 11 different anticonvulsants were identified. Of the 30 instances in which anticonvulsant monotherapy was attempted, carbamazepine, divalproex sodium, lamotrigine, and oxcarbazepine were associated with better psychiatric CGI-I ratings than other monotherapies (P<0.01). Results suggest that in many cases, selected anticonvulsants appeared to simultaneously treat both epilepsy and mood disorder. Controlled trials are necessary to further ascertain optimal anticonvulsant usage.

Levetiracetam as adjunctive antiepileptic therapy for patients with tuberous sclerosis complex: a retrospective open-label trial

Seizures are a common neurologic symptom of tuberous sclerosis complex. The use of levetiracetam as adjunctive antiepileptic therapy was assessed in 20 patients with tuberous sclerosis complex aged 2 to 19 years. In this retrospective evaluation, 40% of patients treated with levetiracetam achieved a seizure reduction of more than 50%. Levetiracetam was generally well tolerated, and adverse events were relatively uncommon in patients who responded to treatment. The most commonly reported adverse events were behavioral problems. Unstable gait, insomnia, poor appetite, and increased seizure frequency were also reported. Based on these results, the use of levetiracetam as adjunctive antiepileptic therapy can reduce seizure frequency in patients with tuberous sclerosis complex. (J Child Neurol 2006;21:53-57).

Effects of Lamotrigine on field potentials, propagation, and long-term potentiation in rat prefrontal cortex in multi-electrode recording

Lamotrigine (LTG) is an anti-epileptic drug that is widely used clinically in various neuropsychiatric disorders. Although consensus is found on the general mode of action by LTG on voltage-gated sodium current, its effect on field potential, neuropropagation, and long-term potentiation, especially in prefrontal cortex (PFC), is still not understood completely. We investigated LTG effects on synaptic response in rat prefrontal cortical slice with the aid of a novel multi-electrode dish (MED64) system. The amplitude and propagation of field excitatory postsynaptic potentials (fEPSP), presynaptic fiber volleys (PrV) were expressed dimensionally in the MED64 system. Lamotrigine (3-100 microM) inhibited the amplitude and propagation of fEPSP and PrV in a concentration dependent manner. It exerted a predominant presynaptic action, as indicated by the increment in paired-pulse facilitation. Stimulating dependency with reduction fEPSP was seen in the presence of LTG at clinically relevant concentrations as well as with PrV, both in amplitude and propagation. In addition, the depression of PrV amplitudes in the presence of LTG showed a use-dependent fashion. As to LTP in PFC, it was not fEPSP amplitude but propagation reduced by LTG. In PFC, LTG exerts its use- and concentration-dependent inhibitory effect on presynaptic action and depresses fEPSP amplitude and propagation in a clinically relevant concentration. LTP was preserved in its fEPSP amplitude but not propagation in PFC in the presence of LTG.

Interactions between Antiepileptic and Antipsychotic Drugs

Antiepileptic and antipsychotic drugs are often prescribed together. Interactions between the drugs may affect both efficacy and toxicity. This is a review of human clinical data on the interactions between the antiepileptic drugs carbamazepine, valproic acid (sodium valproate), vigabatrin, lamotrigine, gabapentin, topiramate, tiagabine, oxcarbazepine, levetiracetam, pregabalin, felbamate, zonisamide, phenobarbital and phenytoin with the antipsychotic drugs risperidone, olanzapine, quetiapine, clozapine, amisulpride, sulpiride, ziprasidone, aripiprazole, haloperidol and chlorpromazine; the limited information on interactions between antiepileptic drugs and zuclopenthixol, periciazine, fluphenazine, flupenthixol and pimozide is also presented. Many of the interactions depend on the induction or inhibition of the cytochrome P450 isoenzymes, but other important mechanisms involve the uridine diphosphate glucuronosyltransferase isoenzymes and protein binding. There is some evidence for the following effects. Carbamazepine decreases the plasma concentrations of both risperidone and its active metabolite. It also decreases concentrations of olanzapine, clozapine, ziprasidone, haloperidol, zuclopenthixol, flupenthixol and probably chlorpromazine and fluphenazine. Quetiapine increases the ratio of carbamazepine epoxide to carbamazepine and this may lead to toxicity. The data on valproic acid are conflicting; it may either increase or decrease clozapine concentrations, and it appears to decrease aripiprazole concentrations. Chlorpromazine possibly increases valproic acid concentrations. Lamotrigine possibly increases clozapine concentrations. Phenobarbital decreases clozapine, haloperidol and chlorpromazine concentrations. Phenytoin decreases quetiapine, clozapine, haloperidol and possibly chlorpromazine concentrations. There are major gaps in the data. In many cases there are no published clinical data on interactions that would be predicted on theoretical grounds.

Family factors and psychopathology in children with epilepsy: a literature review

PURPOSE

From a social interactional and ecological framework, studies were reviewed that (1) compared family factors in children with epilepsy with those in children from normative groups, healthy children, children with a chronic illness, or siblings; and (2) examined the relationship between distinct family factors and child psychopathology.

RESULTS

Compared with control groups, families with a child with epilepsy generally fare worse on the whole range of family factors, indicating lower parent-child relationship quality, more depression in mothers, and problems with family functioning. Significant associations were apparent between distinct family factors, especially parental psychological control, parental attributions about epilepsy, and family members' satisfaction with family relationships, and psychopathology in children with epilepsy.

CONCLUSION

Future childhood epilepsy research might benefit from the examination of the simultaneous contribution of distinct family factors to child psychopathology, within a broad multifactorial framework that also includes neurological and medication factors.

Behavioural effects of the newer antiepileptic drugs: an update

The negative and positive effects of the nine newer antiepileptic drugs that have received a product licence in the UK or in the US are reviewed. The importance of avoiding misinterpretation of the data because of confounding factors such as alternative psychosis, the release phenomenon or drug interactions is emphasised. Vigabatrin has been associated with both psychosis and depression. Due to the concentric visual field defects that may occur with vigabatrin, its use is now limited, although it remains the drug of choice for infantile spasms. Lamotrigine seems to be largely associated with improvement rather than deterioration of mood and behaviour. It may have a role in treating affective disorder. Gabapentin probably has relatively little effect on behaviour but may exacerbate behavioural problems in some children with pre-existing difficulties. Topiramate may precipitate both psychosis and depression, but these are less likely to occur if the currently recommended lower starting doses, escalation rates and target doses are used. The data for tiagabine are limited, but there is no clear evidence for psychosis or depression being caused by this drug. Oxcarbazepine may be of value in treating mood disorder, but the information is very limited. There are few reports of behavioural disturbances with levetiracetam, but the data suggest that there is no significant increase in psychosis or depression. There are some reports of psychosis and other behavioural disturbances with felbamate, but the use of this drug is limited by the serious adverse effects of hepatotoxicity and aplastic anaemia. There is some evidence for psychosis with zonisamide, but there is also a suggestion that this drug may be of benefit in treating psychiatric disorders. Careful individual assessment of each patient should enable the clinician to determine whether the medication or some other factor is responsible for any behavioural disturbance.

Development of mental health dysfunction in childhood epilepsy

A marked prevalence of mental health dysfunction in childhood epilepsy has been documented in the literature. While several individual risk factors have been identified, which are statistically associated with an impaired mental health outcome, there is a lack of knowledge on the pathways taken by these risk factors on disease development and treatment. The relevant literature of the last decade will be reviewed in this paper to provide evidence for the conceptual framework presented here. Thus, the emergence of mental health dysfunction in childhood epilepsy is analyzed under three levels. Pathogenetic causes: These involve both the underlying CNS pathology and the associated epilepsy disorder characterized by specific time of onset duration type and severity. Mediators and moderators connecting causes to outcomes: These comprise, firstly, the differentiation between the intervening role of anti-epileptic drugs and their positive psychotropic impact via suppression of seizure activity and transient cognitive impairments, as against their negative psychotropic side-effects; secondly, the psychological processes of adaptation which entail responding to three major demands (adherence to treatment requirements, exercising self-control and lifestyle modification to reduce seizure activity, and coping with the psychosocial stressors secondary to living with epilepsy); thirdly, the age-dependent level of neurocognitive and behavioral functioning; and, fourthly, contextual risks and protective factors within the family and social environment. Mental health outcome: This encompasses three major domains: risks for learning disability, for impairments of health-related quality of life, and for psychopathology. The proposed framework serves the development and validation of hypotheses and can be applied to testing procedures aimed at investigating the emergence of mental health dysfunction in childhood epilepsy. On the scientific level, it provides an appropriate tool to approach childhood epilepsy in general, whereas on the clinical level, it facilitates the assessment and management of individual patients.

Adverse reactions of Topiramate and Lamotrigine in children

PURPOSE

To review the adverse drug reactions (ADRs) of Topiramate and Lamotrigine among children in Israel, and to compare the two drugs, based on their side effect profile and tolerability among this population.

METHODS

We performed a cross-sectional study. Four paediatric neurologists from three different tertiary medical centres in Israel documented all cases of children from birth to the age 18 years, treated with Topiramate and/or Lamotrigine in their respective outpatient clinics and hospital wards. All present ADRs and their characteristics were recorded.

RESULTS

Reports on 45 and 65 children treated with Topiramate and Lamotrigine respectively, were received. Half of the children treated with Topiramate suffered from one or more ADRs, as opposed to one-third of the children treated with Lamotrigine (p = 0.03). Most reactions were considered mild to moderate. There were no deaths or hospitalisations, but the drug had to be discontinued in about 10% of the patients due to ADRs. Most Topiramate and Lamotrigine ADRs appeared early in the treatment and were more frequent when Topiramate was an add-on versus a monotherapy drug. Most ADRs of both Topiramate and Lamotrigine were related to the central nervous system; while poor appetite, drowsiness, speech difficulties and weight loss were observed only with Topiramate, and rash and headaches only with Lamotrigine. Nervousness and seizure aggravation were more frequent ADRs of Topiramate whereas sleep disturbances were observed more in children treated with Lamotrigine.

CONCLUSION

Results of this study indicate that Lamotrigine causes ADRs less frequently than Topiramate; however both medications are generally well tolerated. Topiramate and Lamotrigine differ in their central nervous system side effect profile.

Attention deficit disorder and epilepsy

Countless studies have demonstrated that patients with epilepsy have a significant increase in behavioral disturbances of all kinds, including hyperactivity and inattention. This finding has been demonstrated in studies utilizing observer questionnaires and behavior rating scales, neuropsychological test batteries, and standardized tests of attention such as continuous performance tests. Multiple factors must be considered in the evaluation of a child with epilepsy and hyperactivity or inattention. For instance, inattention could be due to subclinical seizures, undiagnosed learning disabilities, disturbed sleep as a result of a side effect of antiepileptic medication, or due to an attention deficit disorder. Electroencephalographic monitoring is helpful to distinguish between behavioral inattention and partial complex or absence seizures. Electroencephalographic monitoring can also assess subclinical spike frequency, which may affect attention and other aspects of cognitive functioning in various ways, even in the absence of clinical seizures. Most antiepileptic drugs do not adversely affect attention and behavior in therapeutic doses, with the exception of phenobarbital, gabapentin, and topiramate. Some antiepileptic drugs, such as lamotrigine and carbamazepine, may even have beneficial effects. The preponderance of evidence suggests that stimulants other than bupropion are safe and effective in the treatment of attention deficit disorder in children with epilepsy, although controlled studies of dextroamphetamine in this population are lacking. So far, atomoxetine has not been demonstrated to have any adverse effect in children with epilepsy.

Oxcarbazepine, topiramate, zonisamide, and levetiracetam: potential use in neuropathic pain

BACKGROUND

Oxcarbazepine, topiramate, zonisamide, and levetiracetam are the antiepileptic drugs (AEDs) most recently approved by the US Food and Drug Administration. Based on the experience with carbamazepine, gabapentin, and lamotrigine, these newer AEDs are being investigated for the management of neuropathic pain.

OBJECTIVE

This article reviews preclinical and clinical data on the efficacy and tolerability of these 4 AEDs in the management of neuropathic pain, as well as the pharmacokinetics, drug-interaction potential, adverse effects, and dosing of these agents, with an emphasis on their use in older individuals.

METHODS

Relevant studies were identified through a MEDLINE search of the Englidh-language literature published between 1986 and May 2003, a review of the reference lists of identified articles, and abstracts from the annual meetings of the American Academy of Neurology (1986-2002) and the 2003 Annual Meeting of the American Pain Society. Search terms were oxcarbazepine, topiramate, zonisamide, and levetiracetam.

RESULTS

Oxcarbazepine and topiramate have been effective in animal models of neuropathic pain. Thirty-four publications on the efficacy and tolerability of the 4 agents were identified (25 case reports/case series, 6 randomized parallel-group studies, and 3 randomized crossover studies). The 9 randomized studies were restricted to oxcarbazepine and topiramate, and 23 (68%) publications were available in abstract form only. These preliminary data suggest that the 4 newer AEDs may be useful in a wide variety of neuropathic pain syndromes; however, additional data, including full-length peer-reviewed reports, are necessary before their true analgesic potential in neuropathic pain can be determined. All 4 agents have pharmacodynamic interactions with other psychotherapeutic drugs, potentiating adverse central nervous system events such as sedation. With the exception of levetiracetam, these drugs also have pharmacokinetic interactions with other drugs, although to a somewhat lesser extent than carbamazepine. These agents have some unique adverse effects not frequently monitored by clinicians, such as hyponatremia, nephrolithiasis, acute myopia with secondary angle-closure glaucoma, and weight loss.

CONCLUSIONS

Based on preliminary data, oxcarbazepine, topiramate, zonisamide, and levetiracetam may be useful in the treatment of a wide variety of neuropathic pain syndromes, although full publication of the results of controlled trials is awaited. These agents are associated with specific adverse effects not commonly monitored by clinicians. Of the 4, levetiracetam appears to be easiest to use (ie, no need for dose adjustment in organ dysfunction, no need for laboratory monitoring) and best tolerated, and has not been associated with the unique toxicities seen with oxcarbazepine, topiramate, and zonisamide. The ultimate role of these agents in the therapeutic armamentarium against pain requires further research and experience. In the interim, these 4 agents should be used to treat neuropathic pain in the elderly only when carbamazepine, gabapentin, or lamotrigine cannot be used or when the response to the aforementioned agents is suboptimal.

Effects of antiepileptic medications on psychiatric and behavioral comorbidities in children and adolescents with epilepsy

The three goals of this article are (1) to delineate the limitations in determining the actual incidence of antiepileptic drug (AED) psychiatric and behavioral side effects; (2) to summarize existing data on the direct effects of AEDs on psychiatric and behavioral comorbidities and examine the relationship between these direct effects and specific AED mechanisms of action; and (3) to recognize the indirect effects of AEDs on psychiatric and behavioral medications that can result in aggravation of these comorbidities through drug-drug interactions. All of these data are then combined and formatted into a practical algorithm useful in many clinical situations.

Side Effects of Antiepileptics- A Review

Older generation antiepileptic drugs like Phenobarbital (Luminal), carbamazepine (Tegretol), phenytoin (Dilantin), and valproic acid (Depakote) have several shortcomings such as suboptimal response rates, significant adverse effects, several drug interactions, and a narrow therapeutic index. New antiepileptic drugs have been developed in the last decade to overcome some of these problems. These newer generation antiepileptics like felbamate (Felbatol), gabapentin (Neurontin), lamotrigine (Lamictal), levetiracetam (Keppra), oxcarbazepine (Trileptal), tiagabine (Gabitril), topiramate (Topamax), and zonisamide (Zonegran) have better tolerability profiles, low interaction potential, and significantly less enzyme inducing or inhibiting properties. As the use of antiepileptic drugs has expanded to include treatment of neuropathic pain, newer side effects have been reported. In addition to the common side effects of antiepileptic drugs, like dizziness, drowsiness, and mental slowing; other side effects like weight gain, metabolic acidosis, nephrolithiasis, angle closure glaucoma, skin rash, hepatotoxicity, colitis, and movement and behavioral disorders, to name a few, have been brought to our attention. This review is an attempt to highlight the features and incidences of some of these side effects.

Therapy for neurobehavioral disorders in epilepsy

Neurobehavioral disorders commonly affect patients with epilepsy. In addition to the behavioral changes during and immediately after seizures, the epileptogenic disorder of function often extends further into the postictal and interictal period. Cognitive impairments commonly affect attention, memory, mental speed, and language, as well as executive and social functions. Reducing seizure frequency and the antiepileptic drug burden can reduce these problems. Attentional deficits may respond to therapies for attention-deficit/hyperactivity disorder, but apart from patients with this comorbid disorder, their efficacy is unproven in other epilepsy patients. No effective therapies are established for other cognitive problems, but pragmatic, compensatory strategies can be helpful. Behavioral disorders include fatigue, depression, anxiety, and psychosis. Many of these disorders usually respond well to pharmacotherapy, which can be supplemented by psychotherapy. Cognitive and behavioral disorders can be the greatest cause of morbidity and impaired quality of life, often overshadowing seizures. Yet these problems often go unrecognized and, even when identified, are often undertreated or untreated.