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TYSABRI events are great opportunities to connect with others in your area who are living with relapsing MS. You can learn more about TYSABRI, hear inspirational stories, and get answers to your questions from real experts.
All TYSABRI events are free.
Bring your care partner or a friend along with you. It's a nice way for them to learn more about relapsing MS and expand their support network.
Learn about advice for caregivers... More >>
TYSABRI® (natalizumab) is a prescription medicine used to treat adults with
relapsing forms of multiple sclerosis (MS) to slow the worsening of symptoms common in people with MS and to decrease the
number of flare-ups (relapses). TYSABRI increases the risk of progressive multifocal leukoencephalopathy (PML).
When starting and continuing treatment with TYSABRI, it is important to discuss with your doctor whether the expected
benefit of TYSABRI is enough to outweigh this risk.
Important Safety Information
TYSABRI increases your risk of getting a rare brain infection—called progressive multifocal leukoencephalopathy
(PML)—that usually leads to death or severe disability.
- There is no known treatment, prevention, or cure for PML.
- You should not take certain medicines that weaken your immune system at the same time you are taking TYSABRI.
Even if you use TYSABRI alone to treat your MS, you can still get PML.
- Your risk of getting PML is higher if you:
- have received TYSABRI for a long time, especially for longer than 2 years
- have received certain medicines that can weaken your immune system before you start receiving TYSABRI
- have been infected by the John Cunningham Virus (JCV). Before or while you receive TYSABRI, your doctor may do
a blood test to check if you have been infected by JCV. JCV is a common virus that can cause PML in people who have weakened
immune systems, such as people taking TYSABRI.
- Your risk of getting PML is greatest if you have all 3 risk factors listed above.
There may be other risk factors that have not yet been identified.
- Patients who are anti-JCV antibody negative are still at the risk for the development of PML
due to the potential for a new JCV infection or a false negative test result. Therefore, patients with a
negative test result should be retested periodically.
- While you receive TYSABRI, and for 6 months after you stop receiving TYSABRI, it is important
that you call your doctor right away if you have any new or worsening medical problems (such as problems with
your thinking, eyesight, balance, or strength; weakness on 1 side of your body; and using your arms and legs)
that have lasted several days. Tell all of your doctors that you are getting treatment with TYSABRI.
- Because of your risk of getting PML while you receive TYSABRI, TYSABRI is available only through a
restricted distribution program called the TOUCH® Prescribing Program.
- If you have PML or are allergic to TYSABRI or any of its ingredients, you should not receive TYSABRI.
Before receiving TYSABRI, it is important to tell your doctor:
- If you have a medical condition that can weaken your immune system, such as HIV infection or AIDS, leukemia or lymphoma,
organ transplant, or others, or if you have any new or worsening medical problems that have lasted several days.
- If you are pregnant or plan to become pregnant or if you are breastfeeding or plan to breastfeed.
It is not known if TYSABRI can harm your unborn baby or if the TYSABRI that passes into your breast milk can harm your baby.
- About all of the medicines and supplements you take, especially medicines that can weaken your immune system.
If you are not sure, ask your doctor.
TYSABRI can cause serious side effects. If you have any of the symptoms listed below, call your doctor right away:
Infection of the brain or the covering of your brain and spinal cord
(encephalitis or meningitis) caused by herpes viruses that may lead to death. Symptoms include sudden fever, severe headache, or confusion.
Symptoms of liver damage include yellowing of the skin and eyes (jaundice), unusual darkening of the urine, nausea, feeling tired or weak, or vomiting.
Allergic reactions (eg., hives, itching, trouble breathing, chest pain, dizziness,
wheezing, chills, rash, nausea, flushing of skin, low blood pressure), including serious allergic reactions (eg, anaphylaxis).
Serious allergic reactions usually happen within 2 hours of the start of the infusion, but they can happen any time after receiving TYSABRI.
Weakened immune system.
TYSABRI may increase your risk of getting an unusual or serious infection.
The most common side effects of TYSABRI are:
- Headache, urinary tract infection, lung infection, pain in your arms and legs, vaginitis,
stomach-area pain, feeling tired, joint pain, depression, diarrhea, rash, and nausea.
If you experience any side effect that bothers you or does not go away, tell your doctor.
These are not all of the possible side effects of TYSABRI.
For more information, ask your doctor. To report side effects to FDA, please call 1-800-FDA-1088.
Please see Full Prescribing Information (PDF) including Boxed Warning and Patient Medication Guide (PDF).
This information is not intended to replace discussions with your healthcare provider.