{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T02:03:07Z","timestamp":1788314587959,"version":"build-2803163510"},"reference-count":9,"publisher":"BMJ","issue":"12","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2025,11,28]]},"published-print":{"date-parts":[[2025,12]]},"abstract":"<jats:p>Thyrotoxic periodic paralysis is a rare but potentially life\u2010threatening complication of thyrotoxicosis characterised by hypokalaemia\u2010induced flaccid paralysis due to an intracellular potassium shift rather than total body depletion. We report a male in his early 40s of Filipino origin who awoke with acute bilateral lower\u2010limb weakness after he had consumed a large carbohydrate meal and performed strenuous exercise within the preceding 12 hours. Venous blood gas was normal; initial serum potassium was 1.7\u2009mmol\/L with phosphate 1.07\u2009mmol\/L. The ECG showed sinus tachycardia, first\u2010degree atrioventricular block and prominent U\u2010waves with QTc 388 ms. Urine potassium\/creatinine ratio was 1.7\u2009mmol\/mmol (expected &lt;2.0 in hypokalaemia), indicating appropriate renal conservation. A point\u2010of\u2010care thyroid panel did not include thyroid-stimulating hormone (TSH); the laboratory TSH was reported later as suppressed (0.001 mIU\/L) with elevated FT4\/FT3. There was no diuretic, insulin or \u03b2\u2010agonist use. The patient received potassium chloride totalling 80 mEq (\u226410\u2009mEq\/hour peripherally with continuous ECG monitoring) with serum potassium checks every 1\u20132\u2009hour, and supplementation was stopped once K+ reached 4.0\u2009mmol\/L; propranolol 40\u2009mg orally every 8\u2009hours and methimazole 10\u2009mg orally every 8\u2009hours were started. Muscle strength normalised within 24 hours. This case underscores the diagnostic triad of hypokalaemia without an acid\u2013base disorder, appropriate renal K+ conservation and characteristic ECG changes, and highlights pragmatic dosing\/monitoring plus the need for definitive control of thyrotoxicosis to prevent recurrence.<\/jats:p>","DOI":"10.1136\/bcr-2025-269416","type":"journal-article","created":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T10:40:19Z","timestamp":1765536019000},"page":"e269416","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Thyrotoxic periodic paralysis: diagnostic and management considerations"],"prefix":"10.1136","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-7882-3088","authenticated-orcid":false,"given":"Fahad S","family":"Alrashedi","sequence":"first","affiliation":[{"name":"Internal medicine department, Nephrology section, Ad diriyah hospital, Third riyadh health cluster, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raghad A","family":"Alonazi","sequence":"additional","affiliation":[{"name":"Internal Medicine, Riyadh Third Health Cluster, Riyadh, Riyadh Province, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2025,12,12]]},"reference":[{"key":"2025121202400952000_18.12.e269416.1","doi-asserted-by":"publisher","DOI":"10.1210\/jc.2006-0356"},{"key":"2025121202400952000_18.12.e269416.2","doi-asserted-by":"publisher","DOI":"10.1681\/ASN.2012010046"},{"key":"2025121202400952000_18.12.e269416.3","article-title":"Thyrotoxic Periodic Paralysis: A Unique Case Highlighting the Diagnostic Challenges and Management","volume":"16","author":"Atrash","year":"2024","journal-title":"Cureus"},{"key":"2025121202400952000_18.12.e269416.4","article-title":"Thyrotoxic Periodic Paralysis With Graves\u2019 Disease: A Case Report","volume":"16","author":"Thomas","year":"2024","journal-title":"Cureus"},{"key":"2025121202400952000_18.12.e269416.5","doi-asserted-by":"crossref","first-page":"106","DOI":"10.4103\/ijemcr.ijemcr_44_24","article-title":"Thyrotoxic periodic paralysis: A case series","volume":"2","author":"Reddy","year":"2024","journal-title":"IJEM Case Rep"},{"key":"2025121202400952000_18.12.e269416.6","doi-asserted-by":"crossref","first-page":"105","DOI":"10.4103\/trp.trp_10_24","article-title":"Exploring the enigma of thyrotoxic periodic paralysis","volume":"20","author":"Podimon","year":"2024","journal-title":"Thyroid Res Pract"},{"key":"2025121202400952000_18.12.e269416.7","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0308076","article-title":"A single-center retrospective study on the clinical features of thyrotoxic periodic paralysis","volume":"19","author":"Yamada","year":"2024","journal-title":"PLoS One"},{"key":"2025121202400952000_18.12.e269416.8","first-page":"1030","article-title":"Thyrotoxic periodic paralysis: a case report and review of literature in Saudi Arabia","volume":"31","author":"Al-Moallem","year":"2010","journal-title":"Saudi Med J"},{"key":"2025121202400952000_18.12.e269416.9","first-page":"312","article-title":"Thyrotoxic periodic paralysis in a Saudi male: case report and literature review","volume":"32","author":"Al Shahrani","year":"2012","journal-title":"Ann Saudi Med"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-269416","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T10:40:20Z","timestamp":1765536020000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-269416"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12]]},"references-count":9,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2025,12,12]]},"published-print":{"date-parts":[[2025,12]]}},"alternative-id":["10.1136\/bcr-2025-269416"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-269416","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12]]}}}