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Generic name: fostamatinibFOS-ta-MA-ti-nib ]
Drug class: Miscellaneous coagulation modifiers

Medically reviewed by Philip Thornton, DipPharm. Last updated on Dec 8, 2023.

What is Tavalisse?

Tavalisse belongs to a class of drugs known as spleen tyrosine kinase inhibitors. It works by increasing platelets in your blood.

Tavalisse is used to treat chronic immune thrombocytopenia (ITP), a bleeding condition where the amount of one type of cell in your blood (platelets) is lower than normal.

Tavalisse is given after other treatments have failed. It is not known if this medicine is safe and effective in children.


Tavalisse can raise your blood pressure, sometimes to dangerous levels. Fostamatinib may also cause liver problems, severe diarrhea, and infections.

Tavalisse can make you more likely to get infections or may worsen any current infections. Avoid contact with people who have infections that may spread to others (such as chickenpox, measles, flu). Consult your doctor if you have been exposed to an infection.

Call your doctor if you have: headaches, chest pain, shortness of breath, severe diarrhea, stomach pain, fever, or sore throat.

Before taking this medicine

Tavalisse is not approved for use by anyone younger than 18 years old.

To make sure this medicine is safe for you, tell your doctor if you have ever had:

Do not use Tavalisse if you are pregnant. It could harm the unborn baby. Use effective birth control to prevent pregnancy while you are using this medicine and for at least 1 month after your last dose.

Do not breast-feed while using this medicine, and for at least 1 month after your last dose.

How should I take Tavalisse?

Take Tavalisse exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose..

You may take Tavalisse with or without food.

Fostamatinib can cause diarrhea. You may need to change your diet, drink extra fluids, or take anti-diarrhea medication. Follow your doctor's instructions for treating or preventing diarrhea.

Tavalisse can raise your blood pressure, sometimes to dangerous levels. Your blood pressure will need to be checked often.

You will also need frequent medical tests. Your doctor may change your dose, or you may need to stop using this medicine based on test results.

Store at room temperature away from moisture and heat. Keep the tablets in their original container, along with the packet or canister of moisture-absorbing preservative.

Dosing information

Usual Adult Dose for Thrombocytopenia:

100 mg orally 2 times a day; after a month, if platelet count has not increased to at least 50 x 10(9)/L, increase to 150 mg orally 2 times a day

-This drug may be taken with or without food.
-In the case of a missed dose, instruct patients to take their next dose at its regularly scheduled time.
-Use the lowest dose to achieve and maintain a platelet count at least 50 x 10(9)/L to reduce the risk of bleeding.

Use: For the treatment of thrombocytopenia in adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment

What happens if I miss a dose?

Skip the missed dose and use your next dose at the regular time. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What to avoid

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Tavalisse side effects

Get emergency medical help if you have signs of an allergic reaction to Tavalisse: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

Your Tavalisse doses may be delayed or permanently discontinued if you have certain side effects.

Common Tavalisse side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Tavalisse?

Other drugs may interact with fostamatinib, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Popular FAQ

Tavalisse is used for the treatment of immune thrombocytopenia (ITP) in patients who have had an insufficient response to a previous treatment. Tavalisse (fostamatinib), from Rigel Pharmaceuticals, is an oral spleen tyrosine kinase (SYK) inhibitor.

In ITP, the immune system attacks and destroys the body's own blood platelets which help with blood clotting and healing. Tavalisse blocks an immune signal that can lead to platelet destruction in ITP patients.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Tavalisse only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.