Biochemical, Metabolic, and Hematological Alterations Associated with Serum Carbamazepine Levels in Adult Epileptic Patients: A Cross-Sectional Correlation Study

Abstract Background: Carbamazepine (CBZ) remains one of the most widely used first-line antiepileptic drugs for focal and generalized tonic–clonic seizures. However, chronic CBZ therapy may lead to hepatic, metabolic, and hematological disturbances due to enzyme induction and oxidative stress. Objectives: To evaluate biochemical, metabolic, and hematological alterations in adult epileptic patients receiving CBZ monotherapy and to correlate these parameters with serum CBZ concentrations. Methods: A cross-sectional study was conducted on 96 adult epileptic patients (aged 16–72 years) receiving CBZ 300–800 mg/day for at least 15 days. Serum CBZ levels were measured by High-Performance Liquid Chromatography (HPLC). Biochemical (liver enzymes, renal and lipid profiles, electrolytes) and hematological (hemoglobin, leukocyte, and platelet counts) parameters were assessed. Patients were categorized as subtherapeutic (<4 mg/L), therapeutic (4–12 mg/L), or supratherapeutic (>12 mg/L). Data were analyzed using ANOVA and Pearson’s correlation (p < 0.05). Results: Patients with supratherapeutic CBZ levels exhibited significantly higher AST, ALT, ALP, and bilirubin (p < 0.05) and elevated cholesterol, triglycerides, and LDL levels. Conversely, hemoglobin, leukocyte, platelet counts, and serum sodium decreased with rising CBZ concentration (p < 0.05). Positive correlations were observed between CBZ levels and hepatic/lipid parameters, and negative correlations with hematological indices and sodium. Conclusion: Chronic CBZ therapy induces significant biochemical and hematological alterations, especially at supratherapeutic concentrations. Regular biochemical monitoring alongside therapeutic drug monitoring (TDM) is essential to ensure efficacy, detect toxicity early, and guide individualized dosing.