Investigating seizures in bariatric surgery patients: Pre- and postoperative perspectives: A systematic review

Background Bariatric surgery is widely used for severe obesity and may influence neurological outcomes through metabolic alterations, nutritional deficiencies, and changes in Antiepileptic Drug (AED) absorption. Despite increasing reports of neurological complications, seizure patterns before and after bariatric surgery have not been comprehensively summarized. Methods This was a systematic review conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search of PubMed, Scopus, Web of Science, and Embase was conducted through April 20, 2025. Eighty-three studies reporting seizures before and/or after bariatric surgery were included. Data on patient demographics, surgery type, seizure timing, etiology, AED adjustments, and clinical outcomes were narratively synthesized. Results Across the included studies, patients were mostly middle-aged women undergoing sleeve gastrectomy or Roux-en-Y gastric bypass. Three outcome patterns emerged. Some patients with pre-existing epilepsy remained seizure-free postoperatively with stable AED regimens. Others experienced persistent or recurrent seizures, commonly associated with reduced postoperative absorption of valproate or phenytoin, requiring dose escalation or drug substitution. New-onset postoperative seizures occurred across both surgery types and were predominantly secondary to metabolic disturbances especially hypoglycemia, hyperammonemia, electrolyte abnormalities, or cardiac arrhythmia and typically resolved after addressing the underlying cause. AED adjustments were more frequently required after gastric bypass due to greater pharmacokinetic changes. Conclusion Seizure outcomes after bariatric surgery are variable and influenced by altered drug absorption and postoperative metabolic complications. Most patients maintain seizure control, but a subset develops breakthrough or new-onset seizures, highlighting the need for AED monitoring and careful evaluation of metabolic causes.