Health Library

Fostamatinib (By mouth)

Fostamatinib Disodium (fos-ta-MA-ti-nib dye-SOE-dee-um)

Treats low platelet levels.

Brand Name(s):

When This Medicine Should Not Be Used:

How to Use This Medicine:

Tablet

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
• Missed dose: If you miss a dose of this medicine, skip the missed dose and go back to your regular dosing schedule.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Some medicines can affect how fostamatinib works. Tell your doctor if you are using digoxin or rosuvastatin.

Warnings While Using This Medicine:

• It is not safe to take this medicine during pregnancy. It could harm an unborn baby. Tell your doctor right away if you become pregnant. Use an effective form of birth control during treatment with this medicine and for at least 1 month after the last dose.
• Do not breastfeed during treatment and for at least 1 month after the last dose.
• Tell your doctor if you have liver disease, high blood pressure, or if you had a recent blood clot in your leg or lungs, or any type of infection. Tell your doctor if you have had surgery (including spleen removal).
• This medicine may cause the following problems:
  • High blood pressure
  • Liver problems
• This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Wash your hands often.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
• Dizziness, lightheadedness, fainting
• Severe diarrhea
• Unusual bleeding, bruising, or weakness

If you notice these less serious side effects, talk with your doctor:

• Mild diarrhea

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024