{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T23:24:32Z","timestamp":1787009072671,"version":"build-2736575974"},"reference-count":12,"publisher":"Oxford University Press (OUP)","issue":"1","license":[{"start":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T00:00:00Z","timestamp":1755734400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Guanfacine, a medication used to treat attention-deficit hyperactivity disorder (ADHD), activates alpha-2A adrenergic receptors in the brain to reduce symptoms. However, its central alpha-2 agonist activity can cause adverse events, such as somnolence, bradycardia, and hypotension. We present the case of a 6-year-old boy (15\u2009kg) with no history of regular medication use who was admitted to the hospital with unexplained prolonged somnolence and bradycardia. Initial evaluation ruled out common causes; however, ingestion of his mother\u2019s prescription medication was suspected. Liquid chromatography\u2013quadrupole time-of-flight mass spectrometry confirmed the presence of 6\u2009ng\/mL of guanfacine in his serum, which, together with his symptoms, led to a diagnosis of guanfacine intoxication. To our knowledge, this is the first report of guanfacine intoxication in a young child without ADHD with documented serum concentration measurements. This case may help in the recognition and diagnosis of guanfacine toxicity in pediatric patients.<\/jats:p>","DOI":"10.1093\/jat\/bkaf080","type":"journal-article","created":{"date-parts":[[2025,8,20]],"date-time":"2025-08-20T11:51:04Z","timestamp":1755690664000},"source":"Crossref","is-referenced-by-count":2,"title":["Guanfacine intoxication in a young child presenting with prolonged somnolence and sinus bradycardia: a case report"],"prefix":"10.1093","volume":"50","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0977-5043","authenticated-orcid":false,"given":"Sayaka","family":"Nagasawa","sequence":"first","affiliation":[{"name":"Laboratory of Forensic Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University , 1-8-1 inohana , Chiba city, Chiba, 260-8675,","place":["Japan"]},{"name":"Department of Legal Medicine, Graduate School of Medicine, Chiba University , 1-8-1 inohana , Chiba city, Chiba, 260-8670,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Go","family":"Inokuchi","sequence":"additional","affiliation":[{"name":"Department of Legal Medicine, Graduate School of Medicine, Chiba University , 1-8-1 inohana , Chiba city, Chiba, 260-8670,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minami","family":"Daikai","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Children\u2019s Medical Center, Matsudo City General Hospital , 933-1 sendabori , Matsudo city, Chiba, 270-2296,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroshi","family":"Okada","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Children\u2019s Medical Center, Matsudo City General Hospital , 933-1 sendabori , Matsudo city, Chiba, 270-2296,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hirotaro","family":"Iwase","sequence":"additional","affiliation":[{"name":"Department of Legal Medicine, Graduate School of Medicine, Chiba University , 1-8-1 inohana , Chiba city, Chiba, 260-8670,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2025,8,21]]},"reference":[{"key":"2026041500115144800_bkaf080-B1","doi-asserted-by":"publisher","first-page":"353","DOI":"10.1111\/j.1600-0773.1995.tb00161.x","article-title":"Comparison of the binding activities of some drugs on alpha 2A, alpha 2B and alpha 2C-\u00adadrenoceptors and non-adrenergic imidazoline sites in the Guinea pig","volume":"76","author":"Uhl\u00e9n","year":"1995","journal-title":"Pharmacol Toxicol"},{"key":"2026041500115144800_bkaf080-B2","author":"Takeda Pharmaceutical 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