Background and aims:Crohn's disease (CD) is commonly associated with inflammatory processes located in organs and systems others than the gut, which are known as extraintestinal manifestations (EIM) of the disease. The aim of this study was to assess the effectiveness of adalimumab (ADA) for the treatment of EIM in patients with CD.Methods: forty two consecutive CD patients with at least one EIM were prospectively included in a open-label study. Patients received ADA (160 mg at week zero, 80 mg at week two and 40 mg every other week) over six months and the effectiveness and safety of ADA for EIMs were assessed. The influence of gender, age, smoking habits, family history of inflammatory bowel disease, phenotype and previous anti-TNF treatment on EIM resolution was also investigated.Results: at month six, 76.2% of the patients showed remission or response in CD (33.3% remission and 42.9% any response). EIM showed a parallel course with CD in most cases, and showed remission or response in 66.7% of patients (38.1% remission and 28.5% any response). Patients with any response of their EIM condition were younger than those with no response (p = 0.04). No relationship was found between sex, tobacco, family history of IBD, phenotype and previous treatment with anti-TNF, and EIM resolution.Conclusions: adalimumab is effective in reducing EIM of CD. Age but not tobacco, CD phenotype and anti-TNF-naïve status appears to influence the response.