What's this test for?

This test is ideal if you're experiencing repeated episodes of swelling in your face, hands, feet, throat, or abdomen that come and go without a clear cause like an allergy. It's especially useful if these swelling episodes run in your family or don't respond to typical allergy medications. The test helps identify whether a missing or malfunctioning protein in your blood is behind these symptoms.

What's included in this test?

This test measures a single protein in your blood that helps control swelling and inflammation in your body. Checking its level matters because too little of this protein, or a version that doesn't work properly, can cause the body to swell up without warning in ways that regular allergy testing won't explain.

What happens after I get my results?

Your results will show up in your account with the normal range clearly explained next to your value. If your level comes back low or abnormal, next steps typically include repeating the test to confirm the finding and, if swelling episodes are severe or affect breathing, seeking medical care right away. You can download the full lab report from your account at any time, and if you retest in the future, the trends feature lets you see how your levels change over time.

Who should consider this test?

This test is a good option for people who have recurring, unexplained swelling attacks that don't itch and don't respond to antihistamines. It's also worth considering if a close family member has been diagnosed with hereditary angioedema, since the condition can run in families. People with a history of unexplained abdominal pain attacks alongside swelling may also benefit.

What symptoms indicate I may need this test?

Watch for swelling in your hands, feet, face, lips, or throat that develops over hours and lasts a few days, especially without hives or itching. Sudden, severe abdominal pain, cramping, or nausea that comes in waves can also be a sign, particularly if it happens alongside skin swelling. If these episodes have happened more than once, or a relative has had similar symptoms, it may be worth checking this protein.

How can I naturally support healthy swelling response?

While this protein level is largely determined by genetics, you can help reduce swelling triggers by managing stress, since stress and anxiety can bring on episodes in some people. Avoiding known triggers like minor injuries, certain medications, and excessive physical pressure on the skin may also help. Staying well-hydrated and eating an anti-inflammatory diet rich in fruits, vegetables, and omega-3 fats supports overall inflammation control.

What does low C1 esterase inhibitor mean?

A low level usually means your body isn't making enough of this protein, or it isn't working properly, which can lead to unpredictable swelling episodes. This is the hallmark finding in hereditary angioedema. If your result is low, it's worth tracking your swelling episodes and discussing timing, triggers, and severity so you have clear information for any follow-up testing.

What causes low C1 esterase inhibitor levels?

The most common cause is an inherited genetic mutation passed down from a parent, which is why this condition often runs in families. Less commonly, the protein can become depleted due to certain autoimmune conditions or blood-related disorders that use it up faster than the body can replace it. In rare cases, some medications can also affect its levels.

How often should I retest?

If your first result is normal but you continue having symptoms, retesting during an active swelling episode can be more informative since levels may shift during flare-ups. If you've been diagnosed with a deficiency, periodic retesting (roughly once or twice a year, or as symptoms change) helps you track how your levels are trending. Always retest sooner if your symptoms suddenly worsen or become more frequent.

What should I do if my results are abnormal?

Start by keeping a simple log of your swelling episodes, noting triggers, duration, and severity, since this information is valuable for any follow-up steps. If swelling ever affects your throat or breathing, seek emergency medical care immediately, as this can become dangerous quickly. For non-urgent abnormal results, consider retesting to confirm the finding and share your symptom log with a specialist for further evaluation.

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.

C1 Esterase Inhibitor Test - Swelling & Angioedema Check

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

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