What's this test for?

This test is ideal if you're experiencing unexplained flushing, chronic diarrhea, abdominal cramping, or wheezing that doesn't have a clear cause. These symptoms can sometimes be linked to carcinoid tumors, which are rare growths that release excess serotonin into the blood. This test measures your blood serotonin level to help figure out if that might be happening.

What happens after I get my results?

Your results will show up in your account with your serotonin level and the normal range clearly explained, so you can see exactly where you fall. If your level is high, next steps usually involve retesting and possibly additional imaging tests to check for a tumor, and if your symptoms are severe like ongoing flushing or breathing trouble, you should seek medical care right away. You can download a standard lab report from your account at any time, and if you retest in the future, our trends feature lets you track how your serotonin changes over time.

Who should consider this test?

This test makes sense for anyone with a pattern of unexplained flushing episodes, persistent diarrhea, or wheezing that hasn't been explained by other causes. It's also useful if you have a family history of carcinoid tumors or related conditions and want a baseline blood check. People already being monitored for a known carcinoid tumor may also use this test to track serotonin levels over time.

What symptoms indicate I may need this test?

Common symptoms linked to high serotonin from carcinoid tumors include sudden facial flushing, watery diarrhea, stomach cramping, and wheezing or shortness of breath. Some people also notice a fast heartbeat during flushing episodes. If these symptoms come and go in episodes and don't have an obvious trigger, it may be worth checking your serotonin level.

When will I get my results?

Results are typically ready within about 7 days of your blood draw at the lab. Once ready, they'll be posted directly to your online account, where you can view and download them at your convenience.

What is serotonin and why does it matter?

Serotonin is a chemical made in your gut and brain that helps regulate mood, digestion, and blood vessel function. Most of it is produced in the small intestine, so checking blood serotonin levels can be a useful way to look for gut-related issues, including rare tumors that overproduce it. Keeping serotonin in a healthy range supports normal digestion and stable mood.

What does high serotonin mean?

A high serotonin result can point to a carcinoid tumor, which is a slow-growing growth usually found in the small intestine, appendix, or rectum that releases extra serotonin. It can also occasionally be elevated by certain foods, supplements, or medications taken before the test. If your result is high, retesting after avoiding those factors and getting follow-up imaging are reasonable next steps.

What causes high serotonin levels?

The most common medical cause of high blood serotonin is a carcinoid tumor in the digestive tract. Certain foods high in serotonin precursors, like bananas, walnuts, and pineapple, along with some antidepressant medications, can also temporarily raise levels. Your pre-test instructions on your order confirmation will help you avoid these before your blood draw.

How often should I retest?

If your first result comes back high, retesting after a few weeks—while following any dietary restrictions—can help confirm whether the elevation is real or related to food or medication. If you're being monitored for a known carcinoid tumor, retesting every few months is common to track changes over time. Your trends feature will help you see these changes clearly.

What should I do if my results are abnormal?

If your serotonin level comes back high, start by reviewing whether you ate serotonin-rich foods or took certain medications before your test, since these can affect results. Consider retesting after avoiding those factors for a more accurate picture. If your symptoms are ongoing or severe, such as frequent flushing, diarrhea, or breathing issues, seek medical care to look into the cause further.

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.

Serotonin Blood Test - Carcinoid Tumor Screening

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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