{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T01:30:37Z","timestamp":1771637437857,"version":"3.50.1"},"reference-count":11,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"9","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:p>A 34-year-old man with treatment-resistant schizophrenia and Gilbert\u2019s syndrome was treated with clozapine and found to have unusually slow and fluctuating metabolism of clozapine, resulting in difficulty achieving a well-tolerated and stable plasma clozapine level. Gilbert\u2019s syndrome is a relatively common (3\u201310% prevalence) genetic condition which results in altered hepatic metabolism. This case report demonstrates <jats:italic toggle=\"yes\">in vivo<\/jats:italic> the finding of previous in-vitro research suggesting that the UGT1A1 7\/7 mutation most commonly associated with Gilbert\u2019s syndrome may result in decreased clozapine excretion. Given evidence of an increased prevalence of Gilbert\u2019s syndrome in patients with schizophrenia, further investigation into this possible correlation may improve understanding and prediction of clozapine dosage.<\/jats:p>","DOI":"10.1097\/fpc.0000000000000444","type":"journal-article","created":{"date-parts":[[2021,7,28]],"date-time":"2021-07-28T18:25:34Z","timestamp":1627496734000},"page":"221-224","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":1,"title":["Clozapine metabolism may be affected by Gilbert\u2019s syndrome: case report and discussion"],"prefix":"10.1097","volume":"31","author":[{"given":"Andrea J","family":"Stanbridge","sequence":"first","affiliation":[{"name":"Cumbria, Northumberland Tyne and Wear NHS Foundation Trust"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas","family":"Cranshaw","sequence":"additional","affiliation":[{"name":"Cumbria, Northumberland Tyne and Wear NHS Foundation Trust"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meethu M","family":"Paul","sequence":"additional","affiliation":[{"name":"Cumbria, Northumberland Tyne and Wear NHS Foundation Trust"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"276","published-online":{"date-parts":[[2021,7,26]]},"reference":[{"key":"R1-20250808","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1097\/FPC.0b013e328354026b","article-title":"Glucuronidation of the second-generation antipsychotic clozapine and its active metabolite N-desmethylclozapine. 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