{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T09:38:57Z","timestamp":1785577137077,"version":"3.56.0"},"reference-count":4,"publisher":"Wiley","issue":"4","license":[{"start":{"date-parts":[[2016,1,14]],"date-time":"2016-01-14T00:00:00Z","timestamp":1452729600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"name":"Kentucky Equine Drug Research Council"},{"name":"Racing Medication and Testing Consortium"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vet Pharm &amp; Therapeutics"],"published-print":{"date-parts":[[2016,8]]},"abstract":"<jats:p>Guaifenesin is an expectorant commonly used in performance horses to aid in the clearance of mucus from the airways. Guaifenesin is also a centrally acting skeletal muscle relaxant and as such is a prohibited drug with withdrawal necessary prior to competition. To the authors' knowledge, there are no reports in the literature describing single or multiple oral administrations of guaifenesin in the horse to determine a regulatory threshold and related withdrawal time. Therefore, the objective of the current study was to describe the pharmacokinetics of guaifenesin following oral administration in order to provide data upon which appropriate regulatory recommendations can be established. Nine exercised Thoroughbred horses were administered 2\u00a0g of guaifenesin orally BID for a total of five doses. Blood samples were collected immediately prior to drug administration and at various times postadministration. Serum guaifenesin concentrations were determined and pharmacokinetic parameters calculated. Guaifenesin was rapidly absorbed (<jats:italic>T<\/jats:italic><jats:sub>max<\/jats:sub>of 15\u00a0min) following oral administration. The<jats:italic>C<\/jats:italic><jats:sub>max<\/jats:sub>was 681.3\u00a0\u00b1\u00a0323.8\u00a0ng\/mL and 1080\u00a0\u00b1\u00a0732.8 following the first and last dose, respectively. The serum elimination half\u2010life was 2.62\u00a0\u00b1\u00a01.24\u00a0h. Average serum guaifenesin concentrations remained above the LOQ of the assay (0.5\u00a0ng\/mL) by 48\u00a0h postadministration of the final dose in 3 of 9 horses.<\/jats:p>","DOI":"10.1111\/jvp.12287","type":"journal-article","created":{"date-parts":[[2016,1,14]],"date-time":"2016-01-14T06:40:57Z","timestamp":1452753657000},"page":"416-419","source":"Crossref","is-referenced-by-count":3,"title":["Pharmacokinetics of guaifenesin following administration of multiple doses to exercised Thoroughbred horses"],"prefix":"10.1111","volume":"39","author":[{"given":"H. K.","family":"Knych","sequence":"first","affiliation":[{"name":"K.L. Maddy Analytical Chemistry Laboratory, School of Veterinary Medicine University of California Davis CA USA"},{"name":"Department of Veterinary Molecular Biosciences, School of Veterinary Medicine University of California Davis CA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S. D.","family":"Stanley","sequence":"additional","affiliation":[{"name":"K.L. Maddy Analytical Chemistry Laboratory, School of Veterinary Medicine University of California Davis CA USA"},{"name":"Department of Veterinary Molecular Biosciences, School of Veterinary Medicine University of California Davis CA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D.","family":"Benson","sequence":"additional","affiliation":[{"name":"Racing Medication and Testing Consortium Lexington KY USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R. M.","family":"Arthur","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine University of California, Davis Davis CA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2016,1,14]]},"reference":[{"key":"e_1_2_3_2_1","doi-asserted-by":"crossref","first-page":"469","DOI":"10.2460\/ajvr.1970.31.03.469","article-title":"Pharmacokinetics and metabolism of glyceryl guaiacolate in ponies","volume":"31","author":"Davis L.E.","year":"1970","journal-title":"American Journal of Veterinary Research"},{"key":"e_1_2_3_3_1","doi-asserted-by":"crossref","first-page":"1751","DOI":"10.2460\/ajvr.1980.41.11.1751","article-title":"Guaifenesin: cardiopulmonary effects and plasma concentrations in horses","volume":"41","author":"Hubbell J.A.E.","year":"1980","journal-title":"American Journal of Veterinary Research"},{"key":"e_1_2_3_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.pupt.2008.12.020"},{"key":"e_1_2_3_5_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2885.1997.00081.x"}],"container-title":["Journal of Veterinary Pharmacology and Therapeutics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1111%2Fjvp.12287","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1111%2Fjvp.12287","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/jvp.12287","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,1]],"date-time":"2025-06-01T03:55:34Z","timestamp":1748750134000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/jvp.12287"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,1,14]]},"references-count":4,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2016,8]]}},"alternative-id":["10.1111\/jvp.12287"],"URL":"https:\/\/doi.org\/10.1111\/jvp.12287","archive":["Portico"],"relation":{},"ISSN":["0140-7783","1365-2885"],"issn-type":[{"value":"0140-7783","type":"print"},{"value":"1365-2885","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,1,14]]}}}