Sometimes people with rheumatoid arthritis who are not also taking methotrexate get an injection every week. For those with Crohn's disease and ulcerative colitis, the usual initial dose of Humira is 160 mg on the first one or two days of treatment, followed two weeks later by 80 mg.Two weeks after that, you would probably start a maintenance dose of 40 mg every other week.umira is a type of medication called a tumor necrosis factor (TNF) blocker, or anti-TNF drug. TNF blockers help reduce inflammation and slow the progression of inflammatory conditions by targeting TNF, a substance produced by the immune system that causes inflammation in the body.