{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T23:17:33Z","timestamp":1769037453729,"version":"3.49.0"},"reference-count":25,"publisher":"Oxford University Press (OUP)","issue":"1","license":[{"start":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:00:00Z","timestamp":1768953600000},"content-version":"vor","delay-in-days":20,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,1,21]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Oral and cutaneous ulceration and drug-induced liver injury (DILI) are uncommon adverse drug reactions (ADRs) to leflunomide use in humans. Reports of leflunomide hepatotoxicity in dogs exist but ulceration has not been described in animals. This case series includes a 1.5-year-old male neutered Bernese Mountain Dog, a 7-year-old female spayed Australian Shepherd, and a 1-year-old male neutered mixed-breed dog that were administered leflunomide for immune-mediated conditions. All developed deep ulcerated lesions affecting either the tongue, skin, or both. One dog had concurrent severe DILI. The Naranjo probability scale for ADR suggested the signs were possibly (n\u00a0=\u00a01) or probably (n\u00a0=\u00a02) attributed to leflunomide administration. Ulcerated lesions resolved within weeks and hepatotoxicosis within months after discontinuation of leflunomide administration. This case series indicates that oral and cutaneous ulcers are potential ADRs to leflunomide and provides histological documentation of a leflunomide-induced liver injury.<\/jats:p>","DOI":"10.1093\/jvimsj\/aalaf020","type":"journal-article","created":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T09:04:15Z","timestamp":1768986255000},"source":"Crossref","is-referenced-by-count":0,"title":["Cutaneous and mucosal ulceration associated with the use of leflunomide in three dogs"],"prefix":"10.1093","volume":"40","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-2774-9695","authenticated-orcid":false,"given":"Louis F","family":"Roussille","sequence":"first","affiliation":[{"name":"Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University , North Grafton, MA 01536, United States"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-1003-5932","authenticated-orcid":false,"given":"Elizabeth","family":"Parsley","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University , North Grafton, MA 01536, United States"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4799-3372","authenticated-orcid":false,"given":"Claire L","family":"Fellman","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University , North Grafton, MA 01536, United States"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2026,1,21]]},"reference":[{"key":"2026012104025248600_ref1","doi-asserted-by":"publisher","DOI":"10.1006\/clim.1999.4777","article-title":"Mechanism of action for leflunomide in rheumatoid arthritis","volume":"93","author":"Fox","year":"1999","journal-title":"Clin immunol."},{"key":"2026012104025248600_ref2","doi-asserted-by":"publisher","first-page":"537","DOI":"10.3390\/vetsci11110537","article-title":"Treatment with leflunomide in conjunction with glucocorticoids for dogs with immune-mediated polyarthritis is not associated with improved outcomes: a retrospective cohort study of 93 dogs from Australia (2017\u20132024)","volume":"11","author":"Wilson","year":"2024","journal-title":"Vet Sci"},{"key":"2026012104025248600_ref3","doi-asserted-by":"publisher","DOI":"10.1111\/jsap.13715","article-title":"Retrospective evaluation of leflunomide as an adjunctive therapy in dogs with non-associative immune-mediated thrombocytopenia: 20 cases (2008-2021)","volume":"65","author":"Spear","year":"2024","journal-title":"J Small Anim Pract"},{"key":"2026012104025248600_ref4","doi-asserted-by":"publisher","first-page":"1502","DOI":"10.1111\/jvim.14810","article-title":"A retrospective study on the safety and efficacy of leflunomide in dogs","volume":"31","author":"Sato","year":"2017","journal-title":"J Vet Intern Med"},{"key":"2026012104025248600_ref5","doi-asserted-by":"publisher","first-page":"4143","DOI":"10.1016\/S0041-1345(98)01373-6","article-title":"Leflunomide effectively treats naturally occurring immune-mediated and inflammatory diseases of dogs that are unresponsive to conventional therapy","volume":"30","author":"Gregory","year":"1998","journal-title":"Transplant Proc"},{"key":"2026012104025248600_ref6","doi-asserted-by":"publisher","first-page":"5","DOI":"10.1177\/106002807000400406","article-title":"The role of the hospital","volume":"425","author":"International drug monitoring","year":"1969","journal-title":"World Health Organ Tech Rep Ser"},{"key":"2026012104025248600_ref7","doi-asserted-by":"publisher","first-page":"239","DOI":"10.1038\/clpt.1981.154","article-title":"A method for estimating the probability of adverse drug reactions","volume":"30","author":"Naranjo","year":"1981","journal-title":"Clin Pharmacol Ther"},{"key":"2026012104025248600_ref8","volume-title":"Prescribing information FDA","author":"ARAVA Tablets (Leflunomide)","year":"2011"},{"key":"2026012104025248600_ref9","volume-title":"LiverTox: Clinical and Research Information on Drug-Induced Liver Injury","author":"Hoofnagle JH. 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