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  5. Information on Natalizumab (marketed as Tysabri)
  1. Postmarket Drug Safety Information for Patients and Providers

Information on Natalizumab (marketed as Tysabri)

Natalizumab is used to prevent episodes of symptoms and slow the worsening of disability in patients with relapsing forms (course of disease where symptoms flare up from time to time) of multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control).

Natalizumab is also used to treat and prevent episodes of symptoms in people who have Crohn's disease (a condition in which the body attacks the lining of the digestive tract, causing pain, diarrhea, weight loss, and fever) who have not been helped by other medications or who cannot take other medications.

Natalizumab is in a class of medications called immunomodulators. It works by stopping certain cells of the immune system from reaching the brain and spinal cord and causing damage. 


To report any serious adverse events associated with the use of this drug, please contact the FDA MedWatch program using the contact information at the bottom of this page.

Related Information

Historical Information

Labeling and Regulatory History from Drugs@FDA

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