(HealthDay)—Humira (adalimumab) has been approved by the U.S. Food and Drug Administration to treat moderate-to-severe ulcerative colitis in adults, the agency said Friday.

Humira—an anti- agent that's designed to suppress abnormal inflammatory and immune responses—has already been approved to treat a host of conditions, including , Crohn's disease, and plaque psoriasis.

Ulcerative colitis affects about 620,000 people in the United States, according to the U.S. National Institutes of Health.

The most common side effects of Humira include infection, injection-site reaction, headache, and rash, according to an FDA news release.

The drug is manufactured by Abbott Laboratories, based in North Chicago, Ill.

More information: The U.S. National Library of Medicine has more about ulcerative colitis.