Entyvio (vedolizumab) reduces the effects of a substance in the body that can cause inflammation. Entyvio is used in adults with moderate to severe ulcerative colitis (UC), or moderate to severe Crohn's disease. Entyvio treats active disease and may help keep UC or Crohn's symptoms under control long term. Vedolizumab may also reduce the need for steroid medicines in helping to control symptoms long term.