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Distal RTA (Type 1) is a subtype that specifically results from impaired hydrogen ion secretion and hypokalaemia due to increased potassium loss in the distal nephron, particularly in the collecting duct.<\/jats:p>\n                  <jats:p>Our case describes the clinical course of a middle-aged woman with epilepsy on topiramate monotherapy who presented acutely with flaccid paralysis, areflexia and global hypotonia secondary to critical hypokalaemia. This case highlights the impact of chronic topiramate use on renal physiology, its ability to induce distal RTA and the potential to cause life-threatening hypokalaemia.<\/jats:p>","DOI":"10.1136\/bcr-2025-268105","type":"journal-article","created":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T04:05:23Z","timestamp":1766117123000},"page":"e268105","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Topiramate-induced distal renal tubular acidosis presenting as critical hypokalaemia"],"prefix":"10.1136","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-3655-4918","authenticated-orcid":false,"given":"Anusha","family":"Induraj","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-5461-3625","authenticated-orcid":false,"given":"Mudit","family":"Sharma","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bhushan C","family":"Shetty","sequence":"additional","affiliation":[{"name":"Department of Nephrology, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anubhav","family":"Yadav","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, Karnataka, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2025,12,18]]},"reference":[{"key":"2025121820051607000_18.12.e268105.1","doi-asserted-by":"publisher","DOI":"10.1007\/s40620-021-01032-y"},{"key":"2025121820051607000_18.12.e268105.2","doi-asserted-by":"publisher","DOI":"10.1038\/s41581-023-00699-9"},{"key":"2025121820051607000_18.12.e268105.3","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1093\/ckj\/sfaa017","article-title":"The growing pains of ifosfamide","volume":"13","author":"Sprangers","year":"2020","journal-title":"Clin Kidney J"},{"key":"2025121820051607000_18.12.e268105.4","first-page":"875857","article-title":"Ibuprofen-Induced Hypokalemia and Distal Renal Tubular Acidosis: A Patient\u2019s Perceptions of Over-the-Counter Medications and Their Adverse Effects","volume":"2013","author":"Salter","year":"2013","journal-title":"Case Rep Crit Care"},{"key":"2025121820051607000_18.12.e268105.5","unstructured":"Burger M , Schaller DJ . 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