{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:59:43Z","timestamp":1760061583645,"version":"3.44.0"},"reference-count":10,"publisher":"BMJ","issue":"9","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2025,8,24]]},"published-print":{"date-parts":[[2025,9]]},"abstract":"<jats:p>An athletic male in his 40\u2009s presented to the emergency department following a syncopal episode. He was initially found to be hypoglycaemic at 0.9\u2009mmol\/L and improved clinically with resuscitation and normalisation of blood sugar. Cardiology was consulted, as his ECG showed sinus bradycardia, incomplete right bundle branch block and first-degree heart block. Medical history revealed that the patient took berberine supplements as a performance-enhancing herbal medication. A literature search showed that berberine-induced hypoglycaemia has previously only been reported in patients with diabetes mellitus. Patients can access non-prescription medicines through online websites and social media without medical counselling and oversight. This case highlights the importance of identifying the cause of new unexplained symptomatic hypoglycaemia, a potentially life-threatening scenario. As shown in this case, a thorough medical history, with special emphasis on supplements and over-the-counter medicines, is often paramount. Importantly, there are many normal ECG variants in different populations. Understanding of the normal ECG variants in athletic individuals is important to avoid over-investigation and diagnosis of cardiac disease. To our knowledge, this is the first case of berberine and exercise-induced hypoglycaemia.<\/jats:p>","DOI":"10.1136\/bcr-2025-266876","type":"journal-article","created":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T12:35:22Z","timestamp":1756902922000},"page":"e266876","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Berberine-induced hypoglycaemia and electrocardiogram interpretation in athletes"],"prefix":"10.1136","volume":"18","author":[{"given":"Alexander","family":"Henshall","sequence":"first","affiliation":[{"name":"Cardiology, Buckinghamshire Hospitals NHS Trust, High Wycombe, Buckinghamshire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert","family":"Ambrogetti","sequence":"additional","affiliation":[{"name":"Cardiology, Buckinghamshire Hospitals NHS Trust, High Wycombe, Buckinghamshire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rhys","family":"Pomeroy","sequence":"additional","affiliation":[{"name":"Cardiology, Buckinghamshire Hospitals NHS Trust, High Wycombe, Buckinghamshire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrew","family":"Money-Kyrle","sequence":"additional","affiliation":[{"name":"Cardiology, Buckinghamshire Hospitals NHS Trust, High Wycombe, Buckinghamshire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2025,9,3]]},"reference":[{"key":"2025090305351416000_18.9.e266876.1","doi-asserted-by":"publisher","DOI":"10.1007\/s00125-020-05366-3"},{"key":"2025090305351416000_18.9.e266876.2","doi-asserted-by":"publisher","DOI":"10.1093\/eurheartj\/ehy037"},{"key":"2025090305351416000_18.9.e266876.3","doi-asserted-by":"publisher","DOI":"10.1136\/bjsports-2016-097331"},{"key":"2025090305351416000_18.9.e266876.4","doi-asserted-by":"crossref","unstructured":"Myrissa K , Gayle L , Chohan M , et al . Herbal medicines and dietary supplements\u2019 usage and beliefs among uk adults: a cross-sectional study. European Nutrition Conference; 2024:316. doi:10.3390\/proceedings2023091316","DOI":"10.3390\/proceedings2023091316"},{"key":"2025090305351416000_18.9.e266876.5","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1111\/j.1527-3466.2001.tb00068.x","article-title":"Cardiovascular actions of berberine","volume":"19","author":"Lau","year":"2001","journal-title":"Cardiovasc Drug Rev"},{"key":"2025090305351416000_18.9.e266876.6","doi-asserted-by":"crossref","DOI":"10.1155\/2021\/2074610","article-title":"The Effect of Berberine on Metabolic Profiles in Type 2 Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials","volume":"2021","author":"Guo","year":"2021","journal-title":"Oxid Med Cell Longev"},{"key":"2025090305351416000_18.9.e266876.7","doi-asserted-by":"crossref","unstructured":"Xie W , Su F , Wang G , et al . Glucose-lowering effect of berberine on type 2 diabetes: A systematic review and meta-analysis. Front Pharmacol 2022;13. doi:10.3389\/fphar.2022.1015045","DOI":"10.3389\/fphar.2022.1015045"},{"key":"2025090305351416000_18.9.e266876.8","first-page":"3322","article-title":"Berberine is a potential therapeutic agent for metabolic syndrome via brown adipose tissue activation and metabolism regulation","volume":"10","author":"Hu","year":"2018","journal-title":"Am J Transl Res"},{"key":"2025090305351416000_18.9.e266876.9","doi-asserted-by":"crossref","unstructured":"Mooney R , Simonato P , Ruparelia R , et al . The use of supplements and performance and image enhancing drugs in fitness settings: A exploratory cross\u2010sectional investigation in the United Kingdom. Hum Psychopharmacol 2017;32. doi:10.1002\/hup.2619","DOI":"10.1002\/hup.2619"},{"key":"2025090305351416000_18.9.e266876.10","doi-asserted-by":"crossref","DOI":"10.3389\/fphar.2013.00177","article-title":"The growing use of herbal medicines: issues relating to adverse reactions and challenges in monitoring safety","volume":"4","author":"Ekor","year":"2014","journal-title":"Front Pharmacol"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-266876","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,3]],"date-time":"2025-09-03T12:35:25Z","timestamp":1756902925000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-266876"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9]]},"references-count":10,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2025,9,3]]},"published-print":{"date-parts":[[2025,9]]}},"alternative-id":["10.1136\/bcr-2025-266876"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-266876","relation":{},"ISSN":["1757-790X"],"issn-type":[{"type":"electronic","value":"1757-790X"}],"subject":[],"published":{"date-parts":[[2025,9]]}}}