Pharmacokinetics and Pharmacogenetics of Carbamazepine in Children

Pharmacogenetic Aspects of Drug Metabolizing Enzymes and Transporters in Pediatric Medicine: Study Progress, Clinical Practice and Future Perspectives

As the activity of certain drug metabolizing enzymes or transporter proteins can vary with age, the effect of ontogenetic and genetic variation on the activity of these enzymes is critical for the accurate prediction of treatment outcomes and toxicity in children. This makes pharmacogenetic research in pediatrics particularly important and urgently needed, but also challenging. This review summarizes pharmacogenetic studies on the effects of genetic polymorphisms on pharmacokinetic parameters and clinical outcomes in pediatric populations for certain drugs, which are commonly prescribed by clinicians across multiple therapeutic areas in a general hospital, organized from those with the most to the least pediatric evidence among each drug category. We also further discuss the research status of the gene-guided dosing regimens and clinical implementation of pediatric pharmacogenetics. More and more drug-gene interactions are demonstrated to have clinical validity for children, and pharmacogenomics in pediatrics have shown evidence-based benefits to enhance the efficacy and precision of existing drug dosing regimens in several therapeutic areas. However, the most important limitation to the implementation is the lack of high-quality, rigorous pediatric prospective clinical studies, so adequately powered interventional clinical trials that support incorporation of pharmacogenetics into the care of children are still needed.

Formulation and Characterisation of Carbamazepine Orodispersible 3D-Printed Mini-Tablets for Paediatric Use

One of the main challenges to paediatric drug administration is swallowing difficulties, hindering the acceptability of the medicine and hence clinical outcomes. This study aims at developing a child-appropriate dosage form, the orodispersible mini-tablet (ODMT), using the model drug carbamazepine (CBZ). This dosage form was prepared and 3D-printed via a semi-solid extrusion technique. Design of Experiment methods were applied for optimising the formulation. The formulation with 40% (w/w) of SSG (superdisintegrant) and 5% (w/w) of PVP K30 (binder) was selected and loaded with CBZ. The drug-loaded tablets were characterised by a mean hardness of 18.5 N and a disintegrating time of 84 s, along with acceptable friability. The mean drug loading ratio of the tablets was tested as 90.56%, and the drug release rate in 0.1 M HCl reached 68.3% at 45 min. Excipients showed proper compatibility with the drug in physical form analysis. Taste assessment via an E-tongue was also conducted, where the drug did not show bitter taste signals at a low concentration in the taste assessment, and the sweetener also blocked bitterness signals in the testing. To this end, ODMTs were found to be potential candidates for child-appropriate dosage forms delivering CBZ.

Individualizing doses of antiepileptic drugs

INTRODUCTION

This review aims to identify the optimal therapeutic dosage of anti-epileptic drugs in terms of efficacy and safety in patients with multiple comorbidities.

AREAS COVERED

We have analyzed changes in terms of pharmacokinetics and pharmacodynamics of Brivaracetam, Carbamazepine, Lacosamide, Lamotrigine, Levetiracetam, Topiramate, Valproate, and Zonisamide in liver disease, chronic kidney disease, and in patients admitted to intensive care unit. Our literature search covers the past 5 years. We used PubMed, Google Scholar, and EMBASE database's to support our article.

EXPERT OPINION

To ensure that the patient with seizure receives the best treatment in relation to their comorbidities, careful clinical-laboratory monitoring is necessary to maximize effectiveness while maintaining safety, especially in the case of polytherapy.

Characteristics of infantile convulsions and choreoathetosis syndrome caused by PRRT2 mutation

Importance

Infantile convulsions and choreoathetosis (ICCA) is a rare neurological disorder. Many affected patients are either misdiagnosed or prescribed multiple antiepileptic drugs.

Objective

To explore therapeutic drug treatments and dosages for ICCA in children.

Methods

Detailed clinical features (e.g., past medical history and family history), genetic features, and treatment outcomes were collected from the records of six patients with ICCA.

Results

Mean age at paroxysmal kinesigenic dyskinesia (PKD) onset was 8 years 8 months (range, 3–12 years); the clinical presentation was characterized by daily short paroxysmal episodes of dystonia/dyskinesia. All patients had infantile convulsions at less than 1 year of age, and the mean onset age was 5.5 months (range, 4–7 months). Two patients had a family history of ICCA, PKD, or benign familial infantile epilepsy. Whole exome sequencing identified the c.649–650insC mutation in PRRT2 in six patients; three mutations were inherited and three were de novo. All patients were prescribed low‐dose carbamazepine and showed dramatic improvement with the complete disappearance of dyskinetic episodes after 3 days. They attended follow‐up for 5–17 months and were attack‐free until the final follow‐up.

Interpretation

PRRT2 mutations are the primary cause of ICCA. Low‐dose carbamazepine monotherapy is effective and well‐tolerated in children.

ABCB1 c.3435C > T and EPHX1 c.416A > G polymorphisms influence plasma carbamazepine concentration, metabolism, and pharmacoresistance in epileptic patients

The gene polymorphisms of ABCB1, EPHX1, and SCN1A were found to influence carbamazepine (CBZ) metabolism and resistance in epilepsy patients, but the relevance remains controversial. To reveal the relationships among the gene polymorphisms of ABCB1, EPHX1, SCN1A and the metabolism and resistance of CBZ, the databases of PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, Chinese Science and Technique Journals, China Biology medicine disc and Wan Fang were retrieved for suitable studies up to April 2021. 18 studies containing 3293 epilepsy patients were included. The result revealed the gene polymorphism of ABCB1 c.3435C > T is significantly associated with altered concentration-dose ratios of CBZ (CDR_CBZ) (CC vs. CT, OR = 0.25 (95% CI: 0.08-0.42), P = 0.004), and EPHX c.416A > G gene polymorphism may also significantly adjusted the concentration-dose ratios of carbamazepine-10, 11-trans dihydrodiol (CDR_CBZD) (AA vs. GG, OR = 0.48 (95% CI: 0.01-0.96), P = 0.045; AG vs. GG, OR = 0.68 (95% CI: 0.16-1.20), P = 0.010, respectively) and the ratio of CBZD:carbamazepine-10,11-epoxide (CBZE) (CDR_CBZD:CDR_CBZE) (AG vs GG, OR = 0.83 (95% CI: 0.31-1.36), P = 0.002). Furthermore, ABCB1 c.3435C > T polymorphism was also observed to be significantly influenced CBZ resistance (CC vs TT, OR = 1.78 (95% CI: 1.17-2.72), P = 0.008; CT vs TT, OR = 1.60 (95% CI: 1.12-2.30), P = 0.01; CC + CT vs TT, OR = 1.61 (95% CI: 1.15-2.26), P = 0.006, respectively). Therefore, CBZ metabolism and resistance in patients with epilepsy may be adjusted by the gene polymorphisms of ABCB1 c.3435C > T and EPHX1 c.416A > G which provides the further scientific basis for clinical individualized therapy of epilepsy. However, larger sample size studies are still needed to provide further conclusive evidence.

Carbamazepine-Induced Hematological and Immunological Alterations in Egyptian Children with Idiopathic Generalized Seizures

Carbamazepine (CBZ) is one of the oldest antiepileptic drugs (AEDs) that is still used for the treatment of tonic-clonic seizures in children. Long-term use of AEDs induces potential toxic effects that may remain undetermined for a long time. Earlier studies have revealed a wide spectrum of hematological toxicities associated with CBZ. This study was conducted to unveil the toxic effects of carbamazepine as an antiepileptic monotherapy on hematological and immunological parameters in a group of Egyptian pediatric patients using it for different durations. Fifty pediatric epileptics of either sex were enrolled; 38 were taking CBZ as antiepileptic monotherapy for ≥ 6 months and 12 were newly diagnosed untreated patients. Hematological and immunological parameters studied were compared with their age and sex-matched 15 controls and among groups. CBZ was found more toxic for total leukocyte count, lymphocyte count, serum IgA and IgM levels (p < 0.001, 0.001, < 0.001, < 0.001, respectively). Hemoglobin level, platelets count, serum C4 level and IgA were negatively correlated with serum CBZ level (Spearman's rho = – 0.62, – 0.42, – 0.34, – 0.13; p < 0.001, 0.008, 0.04, 0.44, respectively). CBZ treatment duration associated inversely with platelets, lymphocyte, and eosinophil counts (p < 0.001, 0.03, 0.01, respectively). Epileptic children on CBZ monotherapy had their hematologic and immunologic systems affected, which mandates routine monitoring of these children.

Carbamazepine Levels Related to the Demographic Indicators in Groundwater of Densely Populated Area

Consumption of pharmaceuticals by people is growing. Carbamazepine (CBZ) is an extensively used anti-epileptic drug that is recalcitrant to degradation. As a result, CBZ has been widely detected in the aquatic ecosystem due to its daily consumption and drainage in sewage systems. Leakages from sewage networks and septic tanks may represent one of the main sources of CBZ in groundwater. In this study, CBZ concentrations in groundwater and their correlations with the demographic structure of the population were investigated in the densely populated Milan urban area. Seventy-six demographic variables were retrieved from the Italian Population and Housing census. Twenty-one groundwater samples were collected from unconfined and semi-confined aquifers of the Milan area and the concentration of CBZ was measured. Groundwater CBZ levels in both aquifers were associated with the demographic data within a circular buffer with a radius of 1.5 km. All data were analyzed using a multivariate statistical approach. The results showed a significant association (p < 0.05) between CBZ concentrations and specific demographic segments of the population. Higher CBZ concentrations were found to be associated with the population aged 70 years and over (aging index), and with families having children aged under 5 years (family index). In addition, the divorce index was correlated with the high concentration of CBZ, whereas the educated and sexagenarian population showed a negative correlation. Our results indicated that the contamination of CBZ follows the same pattern in unconfined and semi-confined aquifers, which are used for drinking water purposes in Milan area. Therefore, changing the CBZ consumption pattern or replacing CBZ with other drugs may strongly influence groundwater contamination of the investigated area.

Pharmacogenetics of Carbamazepine and Valproate: Focus on Polymorphisms of Drug Metabolizing Enzymes and Transporters

Pharmacogenomics can identify polymorphisms in genes involved in drug pharmacokinetics and pharmacodynamics determining differences in efficacy and safety and causing inter-individual variability in drug response. Therefore, pharmacogenomics can help clinicians in optimizing therapy based on patient's genotype, also in psychiatric and neurological settings. However, pharmacogenetic screenings for psychotropic drugs are not routinely employed in diagnosis and monitoring of patients treated with mood stabilizers, such as carbamazepine and valproate, because their benefit in clinical practice is still controversial. In this review, we summarize the current knowledge on pharmacogenetic biomarkers of these anticonvulsant drugs.

Current role of carbamazepine and oxcarbazepine in the management of epilepsy

Epilepsy is one of the most common neurological disorders, affecting approximately 50 million people worldwide. Despite a dramatic increase in treatment options over the past 30 years, it still ranks fourth in the world's disease burden. There are now close to 30 antiepileptic drugs (AEDs), with more than two thirds introduced to the market after carbamazepine (CBZ) and one third after its derivative, oxcarbazepine (OXC). Following the introduction of these newer AEDs, the role of CBZ and OXC in the therapeutic armamentarium for seizure control and effective epilepsy management needs to be reviewed. The main guidelines list both CBZ and OXC as first-line options or second-line alternatives for the treatment of focal-onset epilepsy and primary generalized tonic-clonic seizures. While evidence suggests that overall AEDs have similar efficacy, some newer AEDs may be better tolerated than CBZ. In line with this, there have been changes in treatment patterns, with many variations across different countries. However, CBZ remains among the two or three most prescribed drugs for focal epilepsy in many countries, and is widely used across Europe, Africa, South America, and Asia, where it represents a good compromise between cost, availability, and effectiveness. OXC is among the first-choice options for the initial treatment of focal-onset seizures in several countries, including the US and China, where the oral suspension is commonly prescribed. This review provides guidance on the optimal use of these two drugs in clinical practice, including in children, the elderly, and in pregnancy.

Involuntary human exposure to carbamazepine: A cross-sectional study of correlates across the lifespan and dietary spectrum

Treated wastewater (TWW) is increasingly used for agricultural irrigation, especially in arid and semi-arid regions. Carbamazepine is among the most frequently detected pharmaceuticals in TWW. Moreover, its uptake and accumulation have been demonstrated in crops irrigated with TWW. A previous controlled trial found that urine concentrations of carbamazepine were higher in healthy volunteers consuming TWW-irrigated produce as compared to freshwater-irrigated produce. The aim of the current study was to assess whether carbamazepine is quantifiable in urine of Israelis consuming their usual diets and whether concentrations vary according to age, personal characteristics and diet. In this cross-sectional study, we recruited 245 volunteers, including a reference group of omnivorous healthy adults aged 18-66; pregnant women; children aged 3-6 years; adults aged >75 years; and vegetarians/vegans. Participants provided spot urine samples and reported 24-hour and "usual" dietary consumption. Urinary carbamazepine levels were compared according to group, personal characteristics, health behaviors, and reported diet. Carbamazepine was detectable (≥1.66 ng/L) in urine of 84%, 76%, 75.5%, 66%, and 19.6% of the reference group, vegetarians, older adults, pregnant women, and children, respectively. Quantifiable concentrations (≥5.0 ng/L) of carbamazepine were found in 58%, 46%, 36.7%, 14%, and 0% of these groups, respectively (p = 0.001 for comparison of proportions across groups). In adults, higher carbamazepine concentrations were significantly associated (p < 0.05) with self-defined vegetarianism, usual consumption of dairy products and at least five vegetables/day, and no meat or fish consumption in the past 24-hours. This study demonstrates that people living in a water-scarce region with widespread TWW irrigation, are unknowingly exposed to carbamazepine. Individuals adhering to recommended guidelines for daily fresh produce consumption may be at higher risk of exposure to TWW-derived contaminants of emerging concern.

Drug-drug and drug-food interactions in an infant with early-onset SCN2A epilepsy treated with carbamazepine, phenytoin and a ketogenic diet

Sodium channel 2 subunit α (SCN2A) mutations cause difficult-to-treat early-onset epilepsy. Effective treatment includes high-dose phenytoin or carbamazepine ± ketogenic diet (KD). We describe an infant with early-onset SCN2A-epilepsy with subtherapeutic carbamazepine concentration during transition from phenytoin treatment to avoid long-term neurotoxicity. The transition from high-dose phenytoin (20 mg kg^-1 d^-1 , concentration: ≥20 mg/L) with KD, to carbamazepine (50-75 mg kg^-1 d^-1 , concentration: 9-12 mg/L) lasted 85 days, which we suspected was due to significant drug-drug and/or drug-food interactions. Model-based analysis of carbamazepine pharmacokinetics quantified significant time- and dose-dependent phenytoin-mediated CYP3A4 induction and carbamazepine concentration-dependent auto-induction (apparent clearance increased up to 2.5/3-fold). Lower carbamazepine concentrations under KD were modelled as decreased relative bioavailability (44%), potentially related to decreased fraction absorbed (unexpected for this lipophilic drug), increased intestinal/hepatic metabolism and/or decreased protein-binding with KD. This suggests importance of carbamazepine-concentration monitoring during KD-introduction/removal and necessity of high carbamazepine doses to achieve therapeutic concentrations, especially in infants treated with high-dose phenytoin.

Pharmacogenomics of Cognitive Dysfunction and Neuropsychiatric Disorders in Dementia

Symptomatic interventions for patients with dementia involve anti-dementia drugs to improve cognition, psychotropic drugs for the treatment of behavioral disorders (BDs), and different categories of drugs for concomitant disorders. Demented patients may take >6–10 drugs/day with the consequent risk for drug–drug interactions and adverse drug reactions (ADRs >80%) which accelerate cognitive decline. The pharmacoepigenetic machinery is integrated by pathogenic, mechanistic, metabolic, transporter, and pleiotropic genes redundantly and promiscuously regulated by epigenetic mechanisms. CYP2D6, CYP2C9, CYP2C19, and CYP3A4/5 geno-phenotypes are involved in the metabolism of over 90% of drugs currently used in patients with dementia, and only 20% of the population is an extensive metabolizer for this tetragenic cluster. ADRs associated with anti-dementia drugs, antipsychotics, antidepressants, anxiolytics, hypnotics, sedatives, and antiepileptic drugs can be minimized by means of pharmacogenetic screening prior to treatment. These drugs are substrates, inhibitors, or inducers of 58, 37, and 42 enzyme/protein gene products, respectively, and are transported by 40 different protein transporters. APOE is the reference gene in most pharmacogenetic studies. APOE-3 carriers are the best responders and APOE-4 carriers are the worst responders; likewise, CYP2D6-normal metabolizers are the best responders and CYP2D6-poor metabolizers are the worst responders. The incorporation of pharmacogenomic strategies for a personalized treatment in dementia is an effective option to optimize limited therapeutic resources and to reduce unwanted side-effects.

Precision Medicine in Non-Communicable Diseases

The increase in life expectancy during the 20th century ranks as one of society's greatest achievements, with massive growth in the numbers and proportion of the elderly, virtually occurring in every country of the world. The burden of chronic diseases is one of the main consequences of this phenomenon, severely hampering the quality of life of elderly people and challenging the efficiency and sustainability of healthcare systems. Non-communicable diseases (NCDs) are considered a global emergency responsible for over 70% of deaths worldwide. NCDs are also the basis for complex and multifactorial diseases such as hypertension, diabetes, and obesity. The epidemics of NCDs are a consequence of a complex interaction between health, economic growth, and development. This interaction includes the individual genome, the microbiome, the metabolome, the immune status, and environmental factors such as nutritional and chemical exposure. To counteract NCDs, it is therefore essential to develop an innovative, personalized, preventative, early care model through the integration of different molecular profiles of individuals to identify both the critical biomarkers of NCD susceptibility and to discover novel therapeutic targets.

Pharmacogenetics of carbamazepine

Carbamazepine (CMZ) is a drug from the group of anticonvulsants, similar in chemical structure to tricyclic antidepressants. CMZ is widely used for mental disorders and neurological diseases. The lecture discusses the safety of CMZ in respect to personalized medicine, while considering the pharmacogenetic profile of the patient.

The authors declare about the absence of conflict of interest with respect to this publication. All authors contributed equally to this article.

The clinical and genetic spectrum in infants with (an) unprovoked cluster(s) of focal seizures

BACKGROUND

Self-limited (familial) infantile epilepsy (S(F)IE), formerly known as benign (familial) infantile convulsions (B(F)IC), is an infantile cluster epilepsy with in rule a complete recovery. This form of epilepsy is most often caused by variations in the PRRT2 gene (OMIM #605751).

AIM

To describe the clinical and genetic spectrum of sudden onset clusters of focal seizures in infancy.

METHODS

We retrospectively reviewed all individuals, who presented with unprovoked infantile seizures and selected all infants who had unprovoked clustered focal seizures between 1 and 20 months of age. We described the clinical and genetic spectrum of this cohort.

RESULTS

The data of 23 patients from 21 families were collected. All had an initial diagnosis of S(F)IE which was adjusted in 5 individuals. In 12 individuals a pathogenic variation in PRRT2 gene or complete deletion was identified. Pathogenic variants in PCDH19 and KCNQ2 were found in respectively 3 and 1 individuals. One individual had a non-pathogenic variant in ATP1A3 and in 6 others no variants were identified. The mean cluster duration was 2.9 days (range 1-13) (see Table 1). Twelve infants had only one cluster. All patients had focal motor or non-motor seizures, in 12 (52%) followed by bilateral (tonic)clonic seizures. Positive family history was present in 74% of individuals. In 11/12 (92%) tested families, ≥1 family member carried the pathogenic PRRT2 variant. Age of seizure onset (ASO) averaged 6.2 months (range 2-20 months). Age of latest seizure averaged 16 months (range 2-92). In several interictal EEG (electroencephalogram) recordings multifocal spikes or spike-wave abnormalities were detected. Ictal EEG recordings detected primary focal abnormalities.

CONCLUSION

We described 23 individuals with unprovoked cluster(s) of focal seizures at infancy. It appears to be a heterogeneous group. Half of them had a pathogenic variation in PRRT2 gene. Most had only one cluster of seizures. When clusters reoccur frequently, when seizures are more therapy-resistant and when seizures persist beyond the age of 2 years, another diagnosis or causative gene is likely.

Phosphine-Promoted [4 + 3] Annulation of Allenoate with Aziridines for Synthesis of Tetrahydroazepines: Phosphine-Dependent [3 + 3] and [4 + 3] Pathways

In this manuscript, phosphine-dependent [3 + 3] and [4 + 3] annulation reactions of allenoate with aziridines were disclosed. The alkyldiphenylphosphine-promoted [4 + 3] annulation of allenoate with aziridines has been achieved under mild conditions, providing biologically interesting functionalized tetrahydroazepines in moderate to excellent yield with moderate to excellent regioselectivity and diastereoselectivity.

Phosphine-dependent [3 + 3] and [4 + 3] annulation reactions of allenoate with aziridines were disclosed. The alkyldiphenylphosphine-promoted [4 + 3] annulation produced tetrahydroazepines.

Pharmacokinetic considerations for anti-epileptic drugs in children

INTRODUCTION

Epilepsy is a chronic and debilitating neurological disease, with a peak of incidence in the first years of life. Today, the vast armamentarium of antiepileptic drugs (AEDs) available make even more challenging to select the most appropriate AED and establish the most effective dosing regimen. In fact, AEDs pharmacokinetics is under the influence of important age-related factors which cannot be ignored. Areas covered: Physiological changes occurring during development age (different body composition, immature metabolic patterns, reduced renal activity) can significantly modify the pharmacokinetic profile of AEDs (adsorption, volume of distribution, half-life, clearance), leading to an altered treatment response. We reviewed the main pharmacokinetic characteristics of AEDs used in children, focusing on age-related factors which are of relevance when treating this patient population. Expert opinion: To deal with this pharmacokinetic variability, physicians have at their disposal two tools: 1) therapeutic drug concentration monitoring, which may help to set the optimal therapeutic regimen for each patient and to monitor eventual fluctuation, and 2) the use of extended-release drug formulations, when available. In the next future, the development of 'ad-hoc' electronic dashboard systems will represent relevant decision-support tools making the AED therapy even more individualized and precise, especially in children.

Pharmacokinetics and Drug Interaction of Antiepileptic Drugs in Children and Adolescents

Selecting the most appropriate antiepileptic drug (AED) or combination of drugs for each patient and identifying the most suitable therapeutic regimen for their needs is increasingly challenging, especially among pediatric populations. In fact, the pharmacokinetics of several drugs vary widely in children with epilepsy because of age-related factors, which can influence the absorption, distribution, metabolism, and elimination of the pharmacological agent. In addition, individual factors, such as seizure type, associated comorbidities, individual pharmacokinetics, and potential drug interactions, may contribute to large fluctuations in serum drug concentrations and, therefore, clinical response. Therapeutic drug concentration monitoring (TDM) is an essential tool to deal with this complexity, enabling the definition of individual therapeutic concentrations and adaptive control of dosing to minimize drug interactions and prevent loss of efficacy or toxicity. Moreover, pharmacokinetic/pharmacodynamic modelling integrated with dashboard systems have recently been tested in antiepileptic therapy, although more clinical trials are required to support their use in clinical practice. We review the mechanism of action, pharmacokinetics, drug-drug interactions, and safety/tolerability profiles of the main AEDs currently used in children and adolescents, paying particular regard to issues of relevance when treating this patient population. Indications for TDM are provided for each AED as useful support to the clinical management of pediatric patients with epilepsy by optimizing pharmacological therapy.

Effects of Carbamazepine and Valproate on Serum Aspartate Aminotransferase, Alanine Aminotransferase and Gamma - Glutamyltransferase in Children

Introduction:

Epilepsy is one of the most common neurological diseases in childhood and adolescence. Carbamazepine (CBZ) and valproate (VPA) have been widely used as the first generation of antiepileptic drugs (AED).

Aim:

The aim of the study has been to evaluate and compare the effect of CBZ and VPA monotherapy on aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) serum levels in children.

Material and methods:

The study has included 100 patients (boys 57/girls 43, age range 1 to 18 years), who have been treated with CBZ or VPA, as initial monotherapy, for at least 12 months. Patients with liver lesions or patients who have been treated with other drugs have been excluded from the study. The initial serum enzyme levels (AST, ALT and GGT) and after 12 months of treatment have been compared.

Results:

53/100 (53%) patients have been treated with CBZ and 47/100 (47%) patients have been treated with VPA.The initial level of enzymes were within the referece range. After one year-long treatment AST was elevated at 4/53 (7.5%) CBZ patients and 9/47 (19.15%) VPA patients (x2 test =3.965, p<0.05). ALT was elevated at 5/53 (9.4%) CBZ patients and 9/47 (19.15%) VPA patients (x2 test =6.953, p<0.05). GGT was elevated at 18/53 (34%) CBZ patients and 7/47 (14.9%) VPA patients (x2 test =4.831, p<0.05).

Conclusion:

The levels of enzymes AST and ALT have been elevated statistically significant in VPA group and GGT in CBZ group.