Introduction: Tumor necrosis factor (TNF) antagonists are effective therapies for both IBD and psoriasis, though they can paradoxically induce or worsen psoriasis. We aimed to characterize the natural course, prognosis, and treatment of anti-TNF induced psoriasis at a tertiary IBD center. Methods: The UPMC electronic medical record was searched, from March 24, 1994 to May 1, 2012, resulting in 667 IBD patients who received anti-TNF therapy. Each patient chart was then reviewed to confirm diagnoses of IBD and psoriasis, as well as exposure to an anti-TNF agent. A retrospective chart reviewed extracted demographics, clinical variables, medications, and disease activity at each visit. Results: Thirty-three patients with IBD (24 Crohn’s disease (CD), 9 ulcerative colitis (UC)) and psoriasis (14 primary, 19 anti-TNF related) were identified. Psoriasiform lesions occurred in 2.9% of IBD patients exposed to anti-TNF therapy. CD disease location in patients with anti-TNF psoriasis was 57% ileocecal, 29% colonic, 14% ileal, and 14% had perianal disease. For UC, 55% had left-sided disease and 45% had pancolitis. Most patients were white and female (94% and 85%), and were non-smokers (73%). Anti-TNF induced psoriasis was diagnosed a mean of 8.2 years (range, 1-19) after IBD diagnosis, and the mean time to lesion development after anti-TNF therapy initiation was 12.5 months (5-36 months). Psoriasis phenotype was 58% plaque, 16% palmoplantar, 5% pustular, 5% sebopsoriasis, and 16% unknown. Mean length of follow-up was 32 months (0-141 months). At the time of psoriasis onset, 12 patients were receiving infliximab, 6 adalimumab, and 1 certolizumab. Of the patients 14/19 (74%) were receiving anti-TNF monotherapy vs. 5/19 (26%) receiving combination therapy (2 IM, 3 MTX). Of the patients 8/19 (42%) discontinued anti-TNF therapy with improvement in skin symptoms. Three of these patients (37.5%) relapsed when re-challenged with an alternate anti-TNF, while 3 patients (37.5%) tolerated an alternate anti-TNF. Of the patients, 11/19 (58%) remained on their initial anti-TNF agent and/or had adjunctive therapy added to treat psoriasis: 45% MTX, 45% topical corticosteroids (CS), 18% topical CS + calcipotriene, 9% phototherapy. At last follow-up, 11/19 (58%) were receiving anti-TNF (including 5/11 (45%) combination therapy with MTX), 11% MTX, 21% topical CS, 1 ustekinumab. The majority of patients had a decrease in IBD activity following onset of skin lesions. Conclusion: Anti-TNF induced psoriasiform lesions were rare in our cohort, with 58% able to continue anti-TNF therapy with the addition of adjunctive therapies to treat psoriasis. IBD patients in remission who develop anti-TNF induced psoriasis, should be referred to dermatology for alternate treatment options to control their skin disease, and attempt to maintain their anti-TNF regimen.