The impact of demographic and etiological factors on the frequency and severity of side effects of antiepileptic drugs in children Objectives: To examine the relationship between the clinical characteristics of epilepsy, demographic and etiological features, and the number of antiepileptic drugs used in therapy with the severity and incidence of various types of side effects of antiepileptic therapy. Study design: Cross-sectional study with historical data. Patients and Methods: The study involved 370 patients who were examined at the Neuropediatric Clinic of the Pediatric Department of the General County Hospital Požega over a ten-year period (from 2013 to 2023). Out of these, 66 patients who experienced side effects were analyzed. Data on patients and findings were collected from the hospital information system based on the patients' medical histories. Results: The study was conducted on 66 patients with epilepsy who developed side effects from antiepileptic pharmacotherapy, including 30 males and 36 females. The median age was 107 months, ranging from 3 to 207 months. The incidence of adverse effects was 17.84%. Most patients had idiopathic epilepsy (80.3%) and were on monotherapy (83.4%). The most frequently used drug causing side effects was valproate, and the majority of side effects were mild and transient. The most common side effects were cognitive impairments and fatigue/drowsiness. No significant correlation was found between the clinical characteristics of epilepsy, demographic and etiological factors, and the incidence and severity of antiepileptic side effects. Additionally, no differences were found between the number of antiepileptic drugs in therapy concerning the characteristics of side effects. Conclusion: The research results did not confirm a statistically significant difference between children with different demographic characteristics, etiological and clinical features of epilepsy, and the number of drugs in therapy concerning the occurrence and severity of side effects.