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Drugs That Reduce Bowel Inflammation Caused by Crohn Disease

Drugs That Reduce Bowel Inflammation Caused by Crohn Disease


Some Side Effects



  • Sulfasalazine

Common: Nausea, headache, dizziness, fatigue, fever, rash, and, in men, reversible infertility

Uncommon: Inflammation of the liver (hepatitis), pancreas (pancreatitis), or lung (pneumonitis) and hemolytic anemia

Abdominal pain, dizziness, and fatigue are related to dose.

Hepatitis and pancreatitis are unrelated to dose.

  • Balsalazide

  • Mesalamine

  • Olsalazine

Common: Fever and rash

Uncommon: Pancreatitis, inflammation of the pericardium (pericarditis), and pneumonitis

For olsalazine: Watery diarrhea

Most side effects caused by sulfasalazine may occur with any of the other aminosalicylates but much less frequently.



Diabetes mellitus, high blood pressure, cataracts, osteoporosis (decreased bone density), thinning of skin, mental problems, acute psychosis, mood swings, infections, acne, excessive body hair (hirsutism), menstrual irregularities, gastritis, and peptic ulcer disease

Diabetes and high blood pressure are more likely to occur in people who have other risk factors.


Diabetes mellitus, high blood pressure, cataracts, and osteoporosis

Budesonide causes the same side effects as prednisone but to a lesser degree.

Immunomodulating drugs

  • Azathioprine

  • Mercaptopurine

Anorexia, nausea, vomiting, general feeling of illness, infection, cancer, allergic reactions, pancreatitis, low white blood cell count, bone marrow suppression, liver dysfunction, and increased risk of lymphoma

Side effects that are usually dose dependent include bone marrow suppression and liver dysfunction.

Interval blood monitoring is required.


Nausea, vomiting, abdominal distress, headache, rash, soreness of the mouth, fatigue, hair loss, scarring of the liver (cirrhosis), low white blood cell count, and infections

People should take 1 milligram of folic acid daily.

Liver toxicity is likely related to the dose and length of treatment.

Methotrexate also causes abortion and birth defects during pregnancy, so it is not prescribed for pregnant women or women who may become pregnant. Women taking methotrexate should be using an effective method of birth control Immunomodulating drugs Crohn disease is an inflammatory bowel disease where chronic inflammation typically involves the lower part of the small intestine, the large intestine, or both and may affect any part of the... read more Immunomodulating drugs .


High blood pressure, nausea, vomiting, diarrhea, kidney failure, tremors, infections, seizures, neuropathy, and development of lymphomas (cancers of the lymphatic system), headaches, leg cramps, and pins-and-needles sensations

This drug is mainly for people with fistulas.

Side effects become more likely with long-term use.


Similar to cyclosporine

This drug is closely related to cyclosporine and shares a number of its side effects.

Biologic agents


Infusion reactions, infections, cancer, abdominal pain, liver dysfunction, and low white blood cell count

Infusion reactions are potentially immediate side effects that occur during the infusion (such as fever, chills, nausea, headache, itching, rash, hives, decreased blood pressure, or difficulty breathing).

People should be screened for tuberculosis and hepatitis B before initiating treatment.


Pain or itching at the injection site (hypersensitivity reactions), headache, infections, and cancer

Side effects are similar to infliximab except adalimumab is given under the skin (subcutaneously) and so does not cause infusion reactions.

Hypersensitivity reactions that occur at the injection site include pain, rash, itching, and hives. More severe hypersensitivity reactions are possible.


Similar to infliximab and adalimumab

Certolizumab works in a similar way as and causes side effects similar to those of infliximab and adalimumab. It is given subcutaneously.

Some doctors prefer this drug over infliximab and adalimumab for pregnant and nursing women.


Infections and hypersensitivity reactions


Infections, hypersensitivity reactions, and common colds


Infections and hypersensitivity reactions

This drug is given only if treatment with another drug does not work.