Background Tonic-clonic seizures (TCS) have a lot of metabolic processes inside the body, leading to metabolic responses in all systems, including the brain, muscles, liver, kidneys, and blood. This study aimed to differentiate if tonic-clonic seizures were of epileptogenic or non-epileptogenic origin and examine alternative biomarkers for accurate differentiation. Methods Our case-control study was performed in the Pediatrics department at Zagazig University Hospital. A total of 120 individuals were divided into two groups. The first group consisted of children aged six months to fifteen years experiencing tonic-clonic seizures, while the second group included matched healthy children as controls. Blood markers, including lactate, ammonia, and creatine kinase (CK), were analyzed to assess their effectiveness in differentiating between the two groups. Results The study revealed a significant elevation in lactate levels …