Skip to content

Biologics are a type of prescription drug. Your doctor may consider them for you after you've already tried other treatments.

Biologics, which are made from living organisms, work on your immune system. They target specific proteins in your body that cause inflammation.

Other drugs used to treat Crohn’s, such as corticosteroids, suppress your entire immune system and can cause significant side effects. Biologics may have fewer side effects, but some of them can be very serious.

The FDA has approved five biologics to treat Crohn’s disease:

  • Adalimumab (Humira) 
  • Certolizumab pegol (Cimzia)
  • Infliximab (Remicade)
  • Natalizumab (Tysabri)
  • Vedolizumab (Entyvio)

Adalimumab, certolizumab pegol, and infliximab target a protein called TNF-alpha that's involved in inflammation. Natalizumab blocks certain white blood cells in your blood that lead to inflammation. Vedolizumab blocks the inflammatory cells from crossing the blood vessels' walls into areas of inflammation in the gastrointestinal tract. 

Adalimumab (Humira)

This biologic may reduce symptoms of moderate to severe Crohn’s disease in people who haven't responded to standard treatment or to infliximab. Adalimumab may also help keep Crohn’s symptoms from coming back.

How given: injection under the skin

Common side effects:

  • Redness, swelling, itching, pain, rash, or bruising at the injection site
  • Upper respiratory or sinus infections
  • Headache
  • Nausea

Other potential side effects: As with other biologics, adalimumab has the potential for serious side effects, including TB, sepsis, and other infections. In rare cases, people have gotten cancers such as lymphoma.

Certolizumab pegol (Cimzia)

This drug reduces symptoms of moderate to severe Crohn’s disease in people who have not responded to standard treatment. It also helps keeps Crohn’s symptoms from returning.

How given: injection under the skin

Common side effects:

  • Rash
  • Swelling
  • Joint pain
  • Upper respiratory tract infection
  • Urinary tract infection

Other potential side effects: All biologics share the potential for serious side effects, including infections like tuberculosis (TB) and sepsis. These drugs don't cause TB, but they may trigger the infection in people who've already been exposed to the disease. 

You may be vulnerable to other infections as well. Tell your doctor right away if you have an infection, or if you have a cough, fever, fatigue, or the flu. In rare cases, some people have developed certain cancers such as lymphoma.