Hello, 
Humira is a medicine called a 
tumor necrosis factor (TNF) blocker. TNF plays a role in the process that causes inflammation. Because TNF blockers, including HUMIRA, affect the immune system, they can lower the ability to fight infections and may cause other serious side effects.
There is currently no cure for Crohn's disease, and there is no one treatment that works for everyone. The goal of medical treatment is to reduce the inflammation that triggers your sign and symptoms. It is also to improve long term prognosis by limiting complications. In the best cases, this may lead not only to symptom relief but also to long term remission. 
Anti-inflammatory drugs are often the first step in the treatment of Crohn disease including 
corticosteroids such as 
prednisolone or 
budesonide but if not better alone they can use as a combination with an immune system suppressor such as Humira. Also, some Doctor will prescribe Antibiotic can reduce the amount of 
drainage and sometimes heal fistulas and abscesses with Crohn's disease and help reduce harmful intestinal bacteria that may play a role in activating the intestinal immune system, leading to inflammation.
Crohn's disease complication can be painful eye conditions such as uveitis and 
episcleritis. Cause uvea become swollen, the retina swells and vision becomes blurred.
But can cause a serious 
allergic reaction including hives, trouble breathing and swelling of your face, eyes, lips or mouth.
If you have those symptoms you should go to see your doctor right away.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. Heang Chan Raksmey, General & Family Physician