IBD Medication Guide



Brand Name(s)


Drug Class


How taken

Intravenous (IV) infusion

Used for

Moderate-to-severe Crohn’s disease

Recommendations for Pregnancy

Based on animal data, may cause fetal harm

Recommendations for Lactation

Detected in human milk: effects unknown

Medication indication

Reduces signs and symptoms, and induces and maintains clinical remission in adult patients with moderately to severely active Crohn’s disease who have had an inadequate response to conventional therapy, including inhibitors of TNF-alpha.

Indicated for pediatric use

Not indicated for pediatric use

Most common side effects

Infections such as in the urinary tract or upper respiratory tract, headache, tiredness, depression, joint pain, diarrhea, and stomach area pain


Natalizumab increases the risk of progressive multifocal leukoencephalopathy (PML), a rare brain infection that usually causes death or severe disability. Your chance of getting PML increases if you have been exposed to John Cunningham Virus (JCV). Your doctor may do a blood test to check if you have been exposed to JCV before you start receiving natalizumab or during your treatment. The risk of PML is higher in patients who are virus carriers (anti-JCV positive), have received other immunosuppressives, or have been on natalizumab for a long time, especially longer than two years. Natalizumab may also cause liver damage and allergic reactions.

To see the full prescribing information for this medication, click here.

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