What's this test for?

This test is ideal if you're being treated for hemophilia A and need to check whether your body has started fighting off your Factor VIII treatment. It's also useful if you've developed unexplained bleeding problems and a rare autoimmune condition affecting normal clotting is suspected. The test looks for antibodies that can block Factor VIII from doing its job of helping your blood clot properly.

What's included in this test?

This test measures Factor VIII inhibitor activity using a chromogenic assay, a lab method that detects antibodies interfering with normal clotting function. It matters because even small amounts of these antibodies can make standard hemophilia treatment far less effective, so catching them early helps guide better treatment decisions.

What happens after I get my results?

Your results will be available in your account, with the normal range explained alongside your value so you can see exactly where you stand. If an inhibitor is detected, next steps typically involve retesting to track the level over time and adjusting treatment approach, so keep an eye on any new or worsening bruising or bleeding in the meantime. A standard lab report is available for download directly from your account. You can also track your results over time using the trends feature, which is especially helpful for monitoring inhibitor levels across multiple tests.

How can I naturally support healthy blood clotting?

While you can't naturally get rid of a Factor VIII inhibitor, you can support your overall clotting health by staying well hydrated, eating a diet rich in vitamin K (leafy greens) and vitamin C, and avoiding activities with high injury risk. Gentle, low-impact exercise like walking or swimming can help maintain joint health without triggering bleeds. Avoid aspirin, ibuprofen, and other blood-thinning medications unless specifically cleared, since these can worsen bleeding risk on top of an inhibitor.

When will I get my results?

Results are typically ready within about 7 days of your sample being processed at the lab. This test uses a specialized chromogenic assay, which takes a bit longer to run than routine bloodwork, so the extra time helps ensure accuracy. You'll get a notification as soon as your results are posted to your account.

Who should consider this test?

This test is a good fit for anyone diagnosed with hemophilia A who has noticed their usual treatment isn't controlling bleeding as well as it used to. It's also relevant for people who develop sudden, unexplained bruising or bleeding later in life, which can be a sign of an acquired Factor VIII deficiency. If you've recently started or changed Factor VIII replacement therapy, periodic testing can catch inhibitor development early.

What symptoms indicate I may need this test?

Watch for bleeding that's harder to stop than usual, larger or more frequent bruises, joint swelling and pain from internal bleeding, or Factor VIII treatments that suddenly seem less effective. New, unexplained bleeding into muscles or soft tissue in someone without a prior bleeding disorder diagnosis is another key sign. Any of these signs are worth investigating with a blood test sooner rather than later.

What does a high inhibitor level mean?

A high or 'positive' result means your body has developed antibodies that are actively blocking Factor VIII from working, which can make bleeding harder to control even with treatment. The higher the number (measured in Bethesda units), the stronger the antibody response and the more it may interfere with therapy. This is a signal to seek medical care promptly so your bleeding risk can be closely managed.

How often should I retest?

If you're on regular Factor VIII treatment for hemophilia A, periodic testing every few months (or whenever treatment seems less effective) is a reasonable approach to catch inhibitors early. After a positive result, more frequent retesting is often used to track whether the inhibitor level is rising, falling, or responding to changes in treatment. Your testing frequency should be based on your specific bleeding history and treatment plan.

What should I do if my results are abnormal?

If your inhibitor level comes back elevated, seek medical care promptly, especially if you have any active bleeding, swelling, or joint pain. In the meantime, avoid activities that carry injury risk and skip medications like aspirin or NSAIDs that can add to bleeding risk. Keep your lab report handy since it will be useful when discussing treatment adjustments.

Getting your blood test with us is easy, private & backed by the power of science.Long story short: In the test options, use the filters or search box to narrow your choices and find the test you want. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy! If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

How do I know which test to get?

In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option. Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.

When will my lab results be available?

Most test results will be available within 1–3 business days. Once they're ready, we'll send an email and text message to let you know. After your blood draw, just hang tight and don't worry – we'll keep you updated and in the loop! If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com, and we'll gladly help you.

Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?

Absolutely! We totally understand that errors can happen. No worries, we're here to help you. Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you. There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out. Our lab requires an address to be listed to generate an order.

Do you accept health insurance?

Only HSA & FSA is accepted. Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts. This policy applies to all insurance companies, including federal health insurance programs like Medicare. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

Can I cancel my order?

Yes. We get it – sometimes your needs change. As long as your samples haven’t been collected yet, we’re happy to help you cancel your order. If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com. You can read more about our cancellation policy here.

How can I find a lab location near me?

During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp). Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

Factor VIII Inhibitor Panel - Hemophilia A Bleeding Test

Getting your blood test with us is easy, private & backed by the power of science.

Long story short:

In the test options, use the filters or search box to narrow your choices and find the test you want.
If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!

754-799-7833

[email protected]