Inclusion Criteria:~Male or female, 18 years of age or older.~Ulcerative colitis described according to usual criteria, diagnosed for at least 1 year.~Oral maintenance treatment with 5-aminosalicylic acid (5-ASA) only for at least 3 months with a dosage of 2 to 3 g/day.~Clinical remission for at least 3 months (Mayo Clinic score) and endoscopic remission (endoscopic score of Mayo Clinic) at inclusion.~Signed informed consent form.~Exclusion Criteria:~Patients allergic to aspirin or salicylates derivatives~Patients taking the following treatments during the study will be excluded: corticosteroids (oral or rectal route), use of NSAID or Aspirin, any form of sulfasalazine, mesalazine or 4-ASA.~Patients with known significant hepatic or known function abnormalities and/or creatine clearance ≤ 80 ml/min.~Patients with history or physical examination findings indicative of active alcohol or drug abuse.~Women who are pregnant or nursing.~Patients with a history of disease, including mental/emotional disorder that would interfere with their participation in the study.~Patients who participated in another clinical study in the last 3 months.~Patients who are unable to comply with the requirements of the protocol~Female of childbearing potential without efficacious contraception.
Male or female, 18 years of age or older. Ulcerative Colitis described according usual criteria, diagnosed for at least 1 year. Oral maintenance treatment with 5-aminosalicylic acid (5-ASA) only for at least 3 months with a dosage of 2 to 3 g/day. Clinical remission for at least 3 months (Mayo Clinic score) and endoscopic remission (endoscopic score of Mayo Clinic) at the inclusion. Signed informed consent form.