Tavalisse (fostamatinib) is a medication that raises platelet count in adults with immune thrombocytopenia (ITP). It should only be used by people with ITP if other treatments didn't work well. Tavalisse (fostamatinib) is taken by mouth twice daily and can cause side effects such as high blood pressure, infection, and liver problems. It's brand name only, so it can be expensive.
Treatment of long-term immune thrombocytopenia in adults who haven't responded well to other treatments.
Tavalisse (fostamatinib) is a tyrosine kinase inhibitor. When Tavalisse (fostamatinib) blocks tyrosine kinases (a type of protein) in your spleen, it stops antibodies in your immune system from destroying your platelets.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Works well for raising platelet counts in people with ITP
Can be taken with or without food
Available as tablets taken by mouth
Brand name only, which can be expensive
Can't be used in pregnant or nursing females
Commonly causes upset stomach (e.g., diarrhea and nausea) and high blood pressure
Mark your appointments to see your provider or get your lab tests done on your calendar to make sure you're being closely monitored while taking Tavalisse (fostamatinib). You'll need to get tests to check your blood cell count, liver health, and blood pressure regularly while taking this medication.
Tavalisse (fostamatinib) can be taken with or without food.
Tavalisse (fostamatinib) interacts with a lot of medications. Make sure to tell your provider and pharmacist about all the medications you're taking, including over-the-counter medications, vitamins, and supplements, before starting Tavalisse (fostamatinib). Don't start any new medications while taking Tavalisse (fostamatinib) without talking to your provider or pharmacist first. Sometimes, your provider might need to change your dose of Tavalisse (fostamatinib) depending on what other medications you're taking.
Mild-to-moderate diarrhea and nausea are common side effects. Some tips to help treat these include drinking fluids to stay hydrated, having a healthy and balanced diet, and using medications (antidiarrheals or antiemetics) if your provider says it's safe to do so. If you have symptoms of diarrhea or dehydration (e.g., lightheadedness, dizziness, muscle cramps), contact your provider.
Tavalisse (fostamatinib) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: High blood pressure
Tavalisse (fostamatinib) can raise your blood pressure, especially if you already have high blood pressure before starting Tavalisse (fostamatinib). You'll need to monitor your blood pressure every 2 weeks until it seems stable, then you can monitor it once per month. If your blood pressure gets too high while taking the medication, you'll need start taking or change your dose of blood pressure medication. If your blood pressure continues to stay high, you'll need to have your Tavalisse (fostamatinib) dose lowered or you'll need to stop taking Tavalisse (fostamatinib). If you get any symptoms of severe high blood pressure, such as changes in vision, chest pain, bad headache, nausea, vomiting, anxiety, or difficulty breathing, call 911 right away.
If you're pregnant or thinking about becoming pregnant, talk with your provider before taking Tavalisse (fostamatinib) because this medication isn't recommended during pregnancy. Although it hasn't been studied in human pregnancy, it has caused birth defects and death to unborn babies in animal studies. If you’re female and taking this medication (and if you are able to become pregnant), make sure to use birth control while taking Tavalisse (fostamatinib). Continue to use birth control for at least 1 month after your last dose.
If you're having diarrhea or vomiting and you're taking birth control medications by mouth (oral contraceptives), your body might not be absorbing all of your birth control medication, which raises your risk for getting pregnant. If you have vomiting or diarrhea, you should use back-up methods (e.g., condoms or spermicide) and ask your provider about other available types of birth control not taken by mouth.
Although rare, Tavalisse (fostamatinib) might cause liver problems. You'll need to get monthly blood tests to make sure your liver is working properly. If your lab results show signs of liver problems, your provider might temporarily stop your Tavalisse (fostamatinib) in order to figure out whether the medication is causing these problems. Get medical attention right away if you notice signs of liver problems, such as yellowing of your skin or the whites of your eyes, fatigue, low appetite, nausea, stomach discomfort, confusion, or changes in your personality.
Tavalisse (fostamatinib) can lower your white blood cell (WBC) count, which can raise your risk for serious infections. Your provider check your WBC count monthly while you're taking this medication. If it drops too low, your provider will likely have to stop your treatment of or lower your dose of Tavalisse (fostamatinib). Let your provider know right away if you have symptoms of an infection, such as fever, cough, chills, body aches, and tiredness.
Diarrhea is one of the most common side effects caused by Tavalisse (fostamatinib). If you experience diarrhea, talk with your provider right away. You might be able to treat diarrhea with changes to your diet, drinking water to keep hydrated, and taking antidiarrheal medications, such as loperamide (Imodium A-D). But sometimes, your provider might need to lower your dose of Tavalisse (fostamatinib) or stop it all together.
The typical starting dose is 100 mg by mouth twice daily. After 1 month, your provider might raise your dose to 150 mg twice daily, depending on your platelet levels.
Your provider might continue to change your dose depending on your platelet level and whether you're having side effects, such as high blood pressure or diarrhea.
Treatment of long-term immune thrombocytopenia in adults who haven't responded well to other treatments.
Low platelet levels in adults with chronic liver disease (CLD) before a scheduled procedure
Low platelet levels in adults with chronic immune thrombocytopenia (ITP) when other medications haven’t worked
Low platelet count in people with immune thrombocytopenic purpura (ITP) when other medications haven’t worked - adults and children
Low platelet count in people with long-term hepatitis C - adults only
Used alone or with other medications in people who can’t make enough blood cells (severe aplastic anemia) - adults and children
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