BackgroundEpilepsy is a worldwide neurologic illness, characterized by recurrent unprovoked epileptic seizures and can affect people of all age groups. Patients who are receiving drug therapy for chronic diseases, such as epilepsy, must fit complex medication regimens into their everyday routines. Managing medication schedules may pose a significant burden on patients’ lives. Anti-seizure medication choices should therefore be tailored to patients’ factors that may limit medication use. The study aimed to determine the prevalence and Predictors of anti-seizure medication nonadherence among patients with epilepsy. MethodologyAn institutional-based cross-sectional study was conducted among 352 people with epilepsy who were selected by systematic random sampling method at government hospitals in North Shewa Ethiopia. Data were collected by reviewing patients’ charts and interviewing people with epilepsy by using structured and pretested questionnaires. Data obtained were encoded into EPI-INFO software and exported to SPSS version 25 for analysis. Logistic regression was employed to assess independent factors associated with medication non-adherence. ResultThe prevalence of anti-seizure medication non-adherence was 40%. Being female [AOR = 3.37, 95%, CI: 1.84, 6.18], Divorced [AOR = 9.13, 95%, CI: 1.80, 46.34], Being jobless [AOR = 7.33, 95%, CI: 3.24, 16.56], Perceived poor social support [AOR = 2.73, 95%, CI: 1.28, 5.82], perceived stigma [AOR = 5.07, 95%, CI: 2.40, 10.68], polytherapy [AOR = 2.23, 95%, CI: 1.06, 4.71], drug side effects[AOR = 6.03, 95%, CI: 3.17, 11.45], buying medications [AOR = 5.81, 95%, CI: 3.63,16.79] and duration of stay on treatment [AOR = 4.31, 95%, CI: 1.863, 9.97] were significant predictors of anti-seizure medication non-adherence. ConclusionNon-adherence to anti-seizure medication among people with epilepsy in the study area was relatively higher as compared with study reports from different parts of the country. Health and clinical, socio-economy, and patients’ psychological mindset were among the determinant factors affecting the consistency of epilepsy treatment adherence. Enhanced professional, health education for patients as well as for society and financial support, are basic pillars to reduce the constraints of effective treatment.