Adverse Effects Of Valproic Acid Research Articles

L-carnitine for valproic acid-induced toxicity.

Review the effectiveness and dosing of L-carnitine for valproic-acid induced toxicity. A literature review of the pharmacokinetics and clinical use of L-carnitine was performed. Valproic acid is a fatty acid used for numerous therapeutic indications ranging from epilepsy to bipolar disorder. The metabolism of valproic acid produces both therapeutic and toxic metabolites. Whilst it has a good safety profile, adverse effects of valproic acid in chronic use include hepatotoxicity ranging from transient elevation of liver enzymes to fulminant liver failure and hyperammonaemia with resultant encephalopathy. L-carnitine is an essential cofactor for mitochondrial fatty acid metabolism, which is an important source of energy in cardiac and skeletal muscle. Physiological concentrations of L-carnitine are maintained in man by exogenous dietary intake and endogenous synthesis. Following exogenous oral administration of L-carnitine, the bioavailability ranges from 14% to 18%. After bolus intravenous administration of L-carnitine in doses ranging from 20 to 100 mg/kg, the volume of distribution is 0.2-0.3 L/kg, and the fraction excreted unchanged in urine is 0.73-0.95, suggesting that renal clearance of L-carnitine is dose dependent due to saturable renal reabsorption at supraphysiological concentrations. There is evidence supporting the use of L-carnitine in treating hyperammonaemia and hepatotoxicity following chronic therapeutic use and after acute overdose of valproic acid, but the optimal dose and route of administration is unknown. Based on the pharmacokinetics of L-carnitine, we advocate the administration of L-carnitine for valproic-acid induced hyperammonaemia or hepatotoxicity as an intravenous loading dose of 5 mg/kg followed by a continuous intravenous infusion instead of the oral or intravenous boluses that are currently advocated.

Toxicity and teratogenicity effects of valproic acid on zebrafish (Danio rerio) embryos in relation to autism spectrum disorder.

Valproic acid (VPA) is a widely prescribed antiepileptic drug with various medicinal efficacies. Accumulated evidence implied that prenatal exposure to VPA is highly associated with autism spectrum disorder (ASD). In this study, the zebrafish were exposed to a set of VPA concentrations (0, 5, 10, 20, 40, 80, 160, 320, 640, 1280, and 2560 μM) at 5 h post fertilization (hpf) to 120 hpf. The adverse effects of VPA were extensively studied through the evaluations on the mortality, heartbeats, spontaneous tail coiling, and hatching rate. Morphological observations were conducted at 120 hpf, following the exposure termination. Basic locomotor responses and anxiety-like behavioral alterations evaluated for behavioral impairments are the hallmark feature of ASD. The exposure to VPA at teratogenic concentrations reduced the aforementioned parameters in a dose-dependent manner (p ≤ .05). At the selected non-teratogenic concentrations of VPA, the treated larvae demonstrated profound alterations of basic locomotor responses. No significant changes of anxiety and thigmotactic behaviors were observed on the VPA-treated fish compared to the control (p ≥ .005). This study depicted that embryonic zebrafish exposure to VPA produced significant toxicity and teratogenicity effects as well as the alterations of basic behavioral responses. Overall, this study provides a fundamental insight of the toxicity effects at morphological and behavioral levels to facilitate the understanding of ASD mechanisms at different molecular levels.

Valproic Acid Induced Thrombocytopenia and Dysmegakaryopoiesis in a Pediatric Patient

Abstract Introduction/Objective Valproic acid is a branched short chain fatty acid derivative that is used primarily to treat epilepsy as well as mood disorders, certain types of headaches, and neuropathic pain. It is commonly prescribed in the pediatric population and has shown to be effective for refractory epilepsy with adequate seizure control. Serious side effects may be prominent if the medication is not kept at the therapeutic range. A wide variety of known hematologic problems can be encountered including but not limited to anemia, thrombocytopenia, and leukopenia. Methods/Case Report We present a case of a pediatric patient with a past medical history significant for history of seizure disorder and who presented to Jackson Memorial Hospital for intermittent fevers and multiple unexplained bruises for 3 weeks as well as fatigue and weakness.The patient was recently started on valproic acid. Complete blood count (CBC) was obtained and showed a platelet count of 23 x10(3)/mcL with WBC of 3.5 x10(3)/mcL and hemoglobin of 9.7 g/dL.Serum valproate concentration was critically high (154 mg/L). Trephine biopsy showed a normocellular marrow (60%) showing maturing trilineage hematopoiesis and scattered atypical megakaryopoiesis characterized by small forms that are seen in relatively loose interstitial clusters (Figure 1). The marrow aspirate smears were characterized by cellular spicules with dysmegakaryopoiesis including numerous small hypolobated forms with frequent forms showing separated nuclei (Figure 2, 3, and 4). Blasts did not appear increased, comprising overall 1% of marrow cellularity. Karyotype studies revealed a normal female karyotype, 46, XX. FISH studies using probes commonly detected in MDS were negative. Next generation sequencing was negative for AML specific mutations including GATA1 and GATA2 mutations. Results (if a Case Study enter NA) N/A Conclusion This case report highlights the significant hematologic adverse effects of valproic acid, specifically pancytopenia with dysmegakaryopoiesis, raising the clinical suspicion of potential myelodysplastic syndrome. Critically high level of valproic acid (154 mg/L) and normalization of CBC after the stoppage of the medication strongly suggests that valproic acid can cause severe bone marrow suppression and specific morphologic atypia in the megakaryocytic lineage thus introducing a potential diagnostic pitfall. Because the CBC returned to normal, bone marrow biopsy was not repeated.

Antioxidant and anti-inflammatory properties of alpha-lipoic acid protect against valproic acid-induced liver injury.

Valproic acid (VPA) is one of the most used antiepileptic drugs despite of its many adverse effects such as anemia, leucopenia, thrombocytopenia, and liver toxicity. The hepatoprotective effect of alpha-lipoic acid (ALA) was confirmed. The aim of this study was to detect the protective effect of ALA against the adverse effects of VPA. To study this, 30 white albino Wistar male rats were divided into four groups. Group I was the control group; Group II included rats that received ALA (100 mg·kg-1·day-1) orally for 14 days; Group III and Group IV included rats that received VPA (500 mg·kg-1·day-1) for 15 days intraperitoneally, but Group IV rats received ALA (100 mg·kg-1·day-1) orally for 14 days prior to VPA. Blood samples were collected and livers were excised from rats for colorimetric analysis and quantitative real-time PCR. The rats that received VPA showed leucopenia, thrombocytopenia, a significant decrease of superoxide dismutase, glutathione, nuclear factor erythroid 2-related factor 2, and sirtuin 1, besides a significant increase of malondialdehyde and tumor necrosis factor α. Prior treatment with ALA prevented all these results; ALA protected against VPA-induced liver damage and hematological disturbance via antioxidant and anti-inflammatory properties.

Melatonin attenuates branch chain fatty acid induced apoptosis mediated neurodegeneration.

Valproic acid (VPA)-a short branched chain fatty acid (BCFA), is widely recognized as an anticonvulsant and a mood-stabilizing drug, but various adverse effects of VPA have also been investigated. However, the impact of BCFAs aggregation on brain cells, in the pathogenesis of neurodegeneration remains elusive. The objective of this study is to understand the cellular mechanisms underlying VPA-induced neuronal cell death mediated by oxidative stress, and the neuroprotective role of exogenous melatonin treatment on VPA-induced cell death. Neurotoxicity of VPA and protective role exerted by melatonin were assessed in vitro in SH-SY5Y cells and in vivo in the cerebral cortex and cerebellum regions of Wistar rat brain. The results show that melatonin pre-treatment protects the cells from VPA-induced toxicity by exerting an anti-apoptotic and anti-inflammatory effect by regulating apoptotic proteins and pro-inflammatory cytokines. The findings of the present study emphasize novel insights of melatonin as a supplement for the prevention and treatment of neuronal dysfunction induced by VPA.

Perampanel-induced weight gain depends on level of intellectual disability and its serum concentration

BackgroundBody weight (BW) gain may be induced by perampanel (PER) administration, similar to the well-known adverse effects of valproic acid and gabapentin. Intellectual disability (ID) and serum PER concentration may be risk factors of BW gain. PurposeThis study investigated how ID and serum PER concentration are associated with PER-induced BW gain. MethodsSubjects were 76 patients with epilepsy (41 men, aged 16–70 years). All patients were divided by intelligence quotient (IQ) into no ID (IQ ≥ 70, n = 24), mild to moderate ID (70 > IQ ≥35, n = 31), and severe to profound ID (IQ < 35, n = 21) groups. BW was measured before and 2, 4, 6, and 12 months after initiation of PER treatment, and serum PER concentration at 12 months. ResultsBW gains in the mild to moderate ID group at 4, 6, and 12 months were significantly (p < 0.05) higher than in the no ID and in the severe to profound ID groups. At 12 months, BW gain was associated with serum PER concentrations in the no ID (p = 0.034) and the mild to moderate ID (p = 0.001) groups but not in the severe to profound ID group. Multiple linear regression analysis found BW gain at 12 months was positively correlated with the mild to moderate ID group (β = 0.373, p = 0.002) and serum PER concentration (β = 0.241, p = 0.047). ConclusionsThe mild to moderate ID group gained more BW than the no ID group, suggesting that PER-induced food intake was greater due to weaker behavioral control in the mild to moderate ID group. The present study suggests a linear correlation between serum PER concentration and BW change.

Protective effects of melatonin against valproic acid-induced memory impairments and reductions in adult rat hippocampal neurogenesis

Valproic acid (VPA) is widely used in the treatment of epilepsy. However, VPA has been revealed to impair memory of both humans and animals. The adverse effects of VPA are associated with reductions in hippocampal neurogenesis and memory. There are neuroprotective properties exerted by melatonin. Therefore, we investigated the protective effects of melatonin against the reductions of memory and neurogenesis caused by VPA. Male Sprague–Dawley rats received VPA (300 mg/kg) twice a day for 14 days, or melatonin (8 mg/kg/day) for 14 days, or co-treatment with VPA and melatonin for either 14 days (preventive and recovery groups) or 28 days (throughout group). Novel object location and novel object recognition tests were used to assess spatial memory and non-spatial memory, respectively. Proliferation, survival, and immature neurons in the subgranular zone (SGZ) were examined using immunohistochemistry. Rats showed decreases in proliferation, survival, and immature neurons in the SGZ, which were related to impairments in spatial and non-spatial memory. These behavioral changes were prevented by co-administration with melatonin. In addition, the decreasing of the hippocampal neurogenesis was improved to control levels, which had received co-administration with melatonin (preventive, recovery, and throughout). It is noteworthy that rats receiving melatonin alone showed a significant diversity of proliferation, survival and immature neurons compared to the control rats. These findings suggest that melatonin is able to prevent the spatial and non-spatial memory impairments and a reduction in hippocampal neurogenesis simultaneously induced by VPA. Our results provide a feasible way to prevent this loss using melatonin.

Determination of valproic acid and 3-heptanone in plasma using air-assisted liquid-liquid microextraction with the assistance of vortex: Application in the real samples.

Introduction: Valproic acid (VPA) is an antiepileptic drug used to treat epilepsy and bipolar disorder. Adverse effects of VPA were studied in many reports, however, a dose-response relationship between VPA and its metabolites in epilepsy patients are extremely limited. In this paper, a high efficient method was developed for the preconcentration and determination of VPA and its main metabolite in plasma. Methods: For the extraction and preconcentration of the selected analytes, a volume of an extractant was placed at the bottom of the microtube containing pretreated plasma. The mixture was repeatedly withdrawn from the microtube and pushed-out into it using a 1.0-mL glass syringe and resulted in a cloudy mixture. For further turbidity, the mixture was shaken on a vortex agitator. This procedure was used to analyze the plasma samples of patients with epilepsy (n = 70). Results: The results revealed that in most patients with a low level of VPA relative to its expected level, 3-heptanone concentrations were high. The limits of quantification of 3-heptanone and VPA were 0.04 mg L–1 and 0.2 mg L–1, respectively. A suitable precision at a concentration of 2 mg L-1 for each analyte was obtained (relative standard deviation ≤ 9%). Conclusion: The obtained results indicated that this procedure is easy, sensitive, and reliable, and can be used for the analysis of the selected analytes in the plasma samples of patients with epilepsy.

The pharmacogenomics of valproic acid.

Valproic acid is an anticonvulsant and mood-stabilizing drug used primarily in the treatment of epilepsy and bipolar disorder. Adverse effects of valproic acid are rare, but hepatotoxicity is severe in particular in those younger than 2 years old and polytherapy. During valproic acid treatment, it is difficult for prescribers to predict its individual response. Recent advances in the field of pharmacogenomics have indicated variants of candidate genes that affect valproic acid efficacy and safety. In this review, a large number of candidate genes that influence valproic acid pharmacokinetics and pharmacodynamics are discussed, including metabolic enzymes, drug transporters, neurotransmitters and drug targets. Furthermore, pharmacogenomics is an important tool not only in further understanding of interindividual variability but also to assess the therapeutic potential of such variability in drug individualization and therapeutic optimization.

Association of CYP2C9, CYP2A6, ACSM2A, and CPT1A gene polymorphisms with adverse effects of valproic acid in Chinese patients with epilepsy

ObjectiveTo explore the influence of CYP2C9, CYP2A6, ACSM2A, CPT1A gene polymorphisms on valproic acid (VPA) and its role in metabolism-related liver dysfunction in order to guide the clinical safety and rational use of VPA. MethodsOne hundred two patients taking sodium valproate oral solution were genotyped. To assess the genotypes of relevant genes, the CYP2C9 gene was directly sequenced; for polymorphism classification, multiple Long-PCR electrophoresis was conducted for CYP2A6; and imLDR method was used for ACSM2A and CPT1A. GC–MS-SIM was used to determine the levels of VPA and 2-propyl-4-pentenoic acid (4-ene-VPA) in human plasma simultaneously. ResultsCYP2C9 mutations had a significant impact on 4-ene-VPA concentration, in patients with wild-type CYP2C9 (CYP2C9*1), which has a greater capacity for VPA metabolism than the mutant type (CYP2C9*3), liver dysfunction was substantially higher. Patients with an ACSM2A polymorphism had higher levels of ALT and AST compared with wild-type (p<0.05), but the mutations had no effect on the VPA-related liver dysfunction (p>0.05). Among different CYP2A6 and CPT1A genotype groups, there was no significant correlation in the levels of VPA, 4-ene-VPA, ALT, AST or TB (p>0.05). The content of 4-ene-VPA had no direct correlation with the incidence of liver dysfunction. ConclusionsEarly detection of CYP2C9 gene polymorphisms may help to predict or prevent liver dysfunction caused by VPA. While the concentration of 4-ene-VPA was not suitable as an early warning index, the results provide clear theoretical guidance for the rational and safe clinical use of VPA.

The adverse effects of valproic acid on visual functions in the treatment of retinitis pigmentosa.

Purpose:To evaluate the efficacy and safety of valproic acid (VPA) treatment in patients with retinitis pigmentosa (RP).Methods:A total of 48 eyes of 24 patients (13 males, 11 females) with RP prescribed VPA were included. The length of VPA treatment was 6–12 months (mean 9.4 months). Parameters evaluated were best-corrected visual acuity (BCVA) (logarithm of the minimum angle of resolution [logMAR]), visual field analyses (VFAs) with Humprey automated perimetry, multifocal electroretinography (ERG) with Roland-RETI scan, and VPA side effects.Results:Mean age was 34.3 ± 10.3 years (range 18–56 years). Fifteen of the patients (30 eyes) had two ERG and VFA tracings, allowing comparison between baseline and follow-up (range 6–12 months). Mean BCVA before and after VPA therapy was 0.36 ± 0.38 and 0.36 ± 0.37 logMAR, respectively (P = 0.32). Quantitative perimetric indices including mean deviation and pattern standard deviation were not significantly changed after VPA therapy (P > 0.05). P1 amplitudes (in terms of nV/deg2 and mV) of ERG waves were significantly decreased in the rings 1, 3, and 4 after VPA therapy (P < 0.05). Regarding the N1 amplitudes, the only significant decrease was observed in area 1 (P = 0.03). In addition, N1 latency was significantly increased in area 3 after VPA therapy (P = 0.04).Conclusions:VPA therapy did not have any significant benefit on BCVA and VFA. In addition, it may be associated with decline in some ERG parameters. Therefore, physicians should avoid prescribing VPA for RP until its safety and efficacy are appropriately evaluated.

An Evaluation of Peripapillary Retinal Nerve Fiber Layer Thickness in Children With Epilepsy Receiving Treatment of Valproic Acid

AimWe investigated the peripapillary retinal nerve fiber layer thickness with optical coherence tomography in epileptic children receiving valproic acid monotherapy. Materials and methodsThe study was conducted on children aged 8-16 years who were undergoing valproic acid monotherapy for epilepsy. The study group comprised a total of 40 children who met the inclusion criteria and 40 healthy age- and sex-matched children as a control group. Children with at least a 1-year history of epilepsy and taking 10-40 mg/kg/day treatment were included in the study. Peripapillary retinal nerve fiber layer thickness measurements were performed using Cirrus HD optical coherence tomography. All children and parents were informed about the study and informed consent was obtained from the parents of all the participants. ResultsThe study group included 21 girls and 19 boys with a mean age of 10.6 ± 2.3 years. According to the results of optical coherence tomography measurements, the mean peripapillary retinal nerve fiber layer thickness was 91.6 ± 9.7 in the patient group and 95.5 ± 7.4 μm in the control group (P < 0.05). The superior peripapillary retinal nerve fiber layer thickness was 112.0 ± 13.2 in the patient group and 120.0 ± 14.7 μm in the control group (P < 0.02). According to the results of both measurements, the peripapillary retinal nerve fiber layer thickness was significantly lower in the patient group. Neither color vision loss nor visual field examination abnormality could be documented. ConclusionAccording to the optical coherence tomography measurements, the average and superior peripapillary retinal nerve fiber layer thicknesses were thinner in patients with epilepsy who were receiving valproic acid monotherapy compared with healthy children. This situation can lead to undesirable results in terms of eye health. New studies are needed to investigate whether these findings are the result of epilepsy or can be attributed to valproic acid and whether there are adverse effects of valproic acid later in life.

Valproic Acid Induced Isolated Thrombocytopenia after Acute Respiratory Infection

Valproic acid is the most used antiepileptic drug in children. Thrombocytopenia is one of known adverse effects of valproic acid. Acute respiratory infections are the most frequent acute infections in children. We present eleven cases of resistant thrombocytopenia in children on valproic acid therapy within therapeutic levels. Thrombocytopenia (without clinical signs) appeared after a short febrile episodes and signs and symptoms of acute respiratory infection, presenting with only few petehial skin spots. It does not respond to intravenous immunoglobulin’s, nether to corticosteroids. Thrombocytopenia responded dramatically to withdrawing of valproic acid. Complete platelet normalization after valproic acid withdrawal proved known adverse drug reaction between valproic acid and the thrombocytopenia this association.

Stereological investigation of the effects of curcumin on the damage in the hippocampus of developing rat brain caused by valproic acid

Valproic acid is an antiepileptic drug used for the treatment of seizures in newborns, children and adults. Despite having positive effect in the treatment of epilepsy, valproic acid may adversely affect brain function and brain development. Antioxidant and neuroprotective properties of curcumin are well-known. Curcumin has a significant effect in the treatment of various diseases caused by oxidative stress. In the light of this information, the study aimed to determine the adverse effects of valproic acid in the number of pyramidal cells in the hippocampus of the developing rat brain and whether curcumin has protective effects against these adverse effects. A total of 50 Wistar male rats were divided into two groups as 7 and 14 day old. Each group was subdivided into five groups as control, curcumin, dimethyl sulfoxide, valproic acid, valproic acid+curcumin. After dissolving in 10% dimethylsulfoxide, the rats in each group received intraperitoneal injection of valproic acid (400 mg/kg) and curcumin (200 mg/kg). Rats were sacrificed 24 hours after the last injection. After histological processes, stereological analysis was performed using optical fractionation technique. Overall number of neurons in the left hippocampus (CA1, CA2, CA3 and CA4) of the 7 and 14 day old rats was estimated and average numerical values were determined. The mean total neuron numbers and standard deviations for 7 day old rats were 727224±4531.7 in control group; 312232.8±15853.3 in valproic acid group and 431665.4±28464.5 in valproic acid+curcumin group. These numerical values were 508160.6±21985.2; 313958.9±18199.66 and 456028.8±24942.9 for 14 day old rats respectively. The results support the idea that curcumin can be a potential protective and effective agent in the prevention of histological neuronal damage that may occur in the developing rat brain due to valproic acid treatment. We are in the opinion that the results of this study will shed light on clinical studies and form a basis to antioxidant studies involving the use of valproric acid.

Valproic acid and sodium valproate for neuropathic pain and fibromyalgia in adults.

Valproic acid and its sodium salt (sodium valproate) are antiepileptic drugs that are sometimes used to treat chronic neuropathic pain and fibromyalgia, although they are not licensed for this use. To evaluate the analgesic efficacy and adverse effects of valproic acid and sodium valproate in the management of chronic neuropathic pain and fibromyalgia. We identified randomised controlled trials (RCTs) of valproic acid and sodium valproate in acute, and chronic pain by searching MEDLINE, EMBASE and Cochrane CENTRAL to June 2011, together with reference lists of retrieved papers and reviews. RCTs that were double blind and of eight-weeks duration or longer, reporting on analgesic effects and adverse events with valproic acid and sodium valproate in the treatment of chronic neuropathic pain and fibromyalgia. Two review authors independently extracted results and scored for quality. We extracted efficacy and adverse event data, and examined issues of study quality. We included three studies, two in diabetic neuropathy (42 participants treated with valproate, 42 with placebo), and one in post-herpetic neuralgia (23 treated with divalproex sodium, 22 with placebo). Study duration was eight or 12 weeks. No studies were found in fibromyalgia.Only one study reported one of our primary outcomes (≥ 50% pain relief), while all three reported group means for pain reduction from baseline to endpoint. In all three studies; efficacy results were given only for participants who completed the study. One study in diabetic neuropathy and the study in post-herpetic neuralgia reported significant differences between active and placebo groups, but there were insufficient data for reliable pooled analysis.More adverse events were reported with active treatment than placebo, and included nausea, drowsiness and abnormal liver function tests. One participant taking sodium valproate withdrew due to serious derangement of liver enzymes. These three studies no more than hint that sodium valproate may reduce pain in diabetic neuropathy, and divalproex sodium in post-herpetic neuralgia, but the use of 'completer' analysis may overestimate efficacy, and there were too few data for pooled analysis of efficacy or harm, or to have confidence in the results of the individual studies. There is insufficient evidence to support the use of valproic acid or sodium valproate as a first-line treatment for neuropathic pain. There is more robust evidence of greater efficacy for a small number of other drugs.

Long-Term Developmental Outcome of Children of Women with Epilepsy, Unexposed or Exposed Prenatally to Antiepileptic Drugs

Results of studies investigating the long-term effects of intra-uterine exposure to antiepileptic drugs (AEDs) on cognitive functioning are limited and conflicting. To estimate intellectual development of children prenatally exposed or unexposed to AEDs by assessing IQ scores in a systematic review and meta-analysis. A literature search using Pubmed, EMBASE and Google Scholar from inception to 30 April 2009 was performed to identify all original cohort studies that investigated cognitive functioning after in utero exposure to AEDs. Studies had to include at least one group exposed to an AED and one unexposed group. Data from drug exposed and unexposed controls were combined using a random effects model. Eleven studies met the inclusion criteria. Eight studies (three for valproic acid and five for carbamazepine) evaluated IQ as a measure of cognitive development. IQ was assessed by the Wechsler, Bayley or McCarthy intelligence scales, depending on age. One study investigated phenytoin and one study investigated phenobarbital (phenobarbitone). Because one study was reported in two different publications, seven studies were included in the meta-analysis. In total, the seven selected studies included 67 children exposed in utero to valproic acid and 151 exposed to carbamazepine, and 494 unexposed controls born to healthy women or to women with untreated epilepsy. The mean full-scale IQ (FSIQ), verbal IQ (VIQ) and performance IQ (PIQ) scores in children exposed to valproic acid in utero were 83.9 (95% CI 64.2, 103.6), 93.7 (95% CI 72.6, 114.7) and 88.3 (95% CI 69.9, 106.9), respectively. The mean FSIQ, VIQ and PIQ scores in the control group were 102 (95% CI 90, 116), 101 (95% CI 87, 114) and 99 (95% CI 90, 117), respectively. The mean FSIQ, VIQ and PIQ were all significantly lower in the valproic acid group compared with the unexposed group. The FSIQ and VIQ of children exposed to carbamazepine were not statistically different from those of the unexposed control group. In a sub-analysis of carbamazepine exposure in three studies using the Wechsler intelligence scale, PIQ was significantly lower in children exposed to carbamazepine than in unexposed children. Although our analysis revealed no evidence that untreated maternal epilepsy was associated with a lower IQ in the child, there may have been confounding factors, such as milder epilepsy, in this group. Exposure to valproic acid in pregnancy is associated with significantly reduced intelligence in children whose mothers were treated for epilepsy. Exposure to carbamazepine in pregnancy does not appear to be associated with reduced FSIQ and VIQ in children, although PIQ was lower in the sub-analysis. Clinicians should inform families of the potential cognitive adverse effects of valproic acid. More studies are needed to corroborate these findings.

Adult-onset of Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-Like Episodes (MELAS) Syndrome Presenting as Acute Meningoencephalitis: A Case Report

Background: Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare mitochondrial disorder with a wide range of multisystemic symptoms. Epileptic seizures are common features of both MELAS and meningoencephalitis and are typically treated with anticonvulsants. Objectives: To provide the reader with a better understanding of MELAS and the adverse effects of valproic acid. Case Report: A 47-year-old man with a history of diabetes, hearing loss, sinusitis, and otitis media was brought to our emergency department due to acute onset of fever, headache, generalized seizure, and agitation. Because acute meningoencephalitis was suspected, the patient was treated with antibiotics on an empirical basis. The seizure activity was aggravated by valproic acid and abated after its discontinuation. MELAS was suspected and the diagnosis was confirmed by the presence of a nucleotide 3243 A→G mutation in the mitochondrial DNA. Conclusion: Detailed history-taking and systematic review help emergency physicians differentiate MELAS from meningoencephalitis in patients with the common presentation of epileptic seizures. Use of valproic acid to treat epilepsy in patients suspected of having mitochondrial disease should be avoided. Underlying mitochondrial disease should be suspected if seizure activity worsens with valproic acid therapy.

Effects of valproic acid on hearing in epileptic patients

Since some case reports about the ototoxicity of valproic acid have been published, probable adverse effects of valproic acid on hearing in the epileptic patients became a subject of interest. We wanted to investigate if ototoxicity occurs in pediatric epileptic patients using VPA for long terms. Twenty-one epileptic patients who have been using valproic acid at least for 6 months as monotherapy and 21 age-sex matched controls were included in the study. Audiometric tests were performed to all patients between the frequencies of 125 and 16,000 Hz. The effects of dosage, duration of therapy and serum levels of the VPA, on the audiometric results were investigated and the audiometric results were compared between the groups. There was no difference in hearing thresholds of the groups between 125 and 16,000 Hz frequencies. Relation could not be established between the duration of VPA therapy, dosage of the drug, blood level of drug, age and sex of the patients and the auditory signs. Although we could not find any deleterious effect of VPA on hearing thresholds in our patient series, we think it is useful to perform audiometric tests at intervals while VPA is being used for long periods, considering the presented case reports about sensorineural hearing loss.

Amelioration of adverse effects of valproic acid on ketogenesis and liver coenzyme A metabolism by cotreatment with pantothenate and carnitine in developing mice: possible clinical significance.

Very young children with organic brain damage, intractable seizures, and developmental retardation are at particular risk of developing fatal hepatic dysfunction coincident with valproate therapy, especially if the children are also receiving other anticonvulsant drugs. The mechanism of valproate-associated hepatic failure in these children is unclear. There are two major theories of etiology. The first concerns the manyfold consequences of depletion of CoA due to sequestration into poorly metabolized valproyl CoA and valproyl CoA metabolites. The other theory proposes that the unsaturated valproate derivative 2-n-propyl-4-pentenoic acid and/or metabolically activated intermediates are toxic and directly cause irreversible inhibition of enzymes of beta-oxidation. The present study shows for the first time that in developing mice, when panthothenic acid and carnitine are administered with valproate, at least some of the effects of valproate are mitigated. Perhaps most importantly, the beta-hydroxybutyrate concentration in plasma and the free CoA and acetyl CoA levels in liver do not fall so low. Cotreatment with carnitine alone was without effect. Findings support the CoA depletion mechanism of valproate inhibition of beta-oxidation and other CoA- and acetyl CoA-requiring enzymic reactions and stress the role of carnitine in the regulation of CoA synthesis at the site of action of pantothenate kinase.

Effect of associated antiepileptic treatment on valproate-induced hyperammonemia.

It has recently been shown that acute changes of venous blood ammonia (NH3) may predict short-term adverse effects of valproic acid (VPA). In the present study, the time course of NH3 concentration after a single oral dose of VPA (800 mg) was monitored in 68 epileptic patients. Patients were classified into four groups: previously untreated patients (group A, n = 21), patients under treatment with either phenobarbital (group B, n = 14) or phenytoin (group C, n = 13) or both (group D, n = 20). In each patient, venous blood for the NH3 assay was taken before the VPA dose (predose level) and at 1, 2, 3, and 4 h after the dose (postdose levels). While in patients receiving only VPA the postdose NH3 concentrations did not differ from the predose level, in each of groups B, C, and D the postdose concentrations appeared to be significantly higher than the predose concentration. The greatest increase was observed in group D. In the light of the data reported in the literature, those patients whose NH3 concentration after the VPA dose exceeds 100 micrograms/dl should be considered at higher risk for short-term, VPA-induced adverse effects during long-term therapy. Thus, our data suggest that caution should be exercised in adding VPA to anticonvulsant treatments including phenobarbital or phenytoin or both.