POTS Disease: What It Is, Why It Happens, and Why Your Tests May Look Normal
Written and reviewed by Dr. Sam McDonald, DC · Colorado License CHR.0007574 · NPI 1770001588 · Omega Functional Health
You stand up and your heart takes off. The room tilts. Your vision dims at the edges, and for a few seconds you wonder if you are going to make it to the counter.
Then come the rest of the symptoms. The exhaustion that sleep does not fix. The brain fog. The shower that leaves you needing to lie down.
If you have been told you have POTS disease, or you suspect you might, you have probably also been told something else: that your tests look normal. This article explains what POTS is, why it happens, and why “normal” tests do not always mean nothing is wrong.
What is POTS disease?
POTS stands for postural orthostatic tachycardia syndrome. It is not technically a disease. It is a syndrome, a recognizable cluster of symptoms, and it is one of the most common forms of dysautonomia, which means a problem with the autonomic nervous system.
Your autonomic nervous system runs everything you do not think about: heart rate, blood pressure, blood vessel tone, digestion, and temperature. When you stand up, gravity pulls blood toward your legs. In a well-regulated system, your brain senses that shift within seconds and tightens your blood vessels so blood keeps reaching your head.
In POTS, that adjustment does not happen smoothly. The heart speeds up to make up for it. Doctors usually diagnose POTS when heart rate rises by at least 30 beats per minute within 10 minutes of standing (40 for teens), without a large drop in blood pressure, along with symptoms that have lasted for months.
What does POTS feel like?
POTS symptoms often go well beyond a fast heartbeat. Common ones include:
- A racing or pounding heart when standing
- Lightheadedness, dizziness, or nearly fainting
- Fatigue that rest does not fully relieve
- Brain fog and trouble concentrating
- Headaches, often at the back of the head or neck
- Nausea and other digestive problems
- Shakiness, sweating, or feeling anxious without a reason
- Trouble tolerating heat, long showers, or standing in line
POTS most often affects women between their teens and their forties, though men and older adults can have it too. It often starts after a viral illness, a concussion, surgery, pregnancy, or a period of major stress. Many people with POTS also have hypermobile Ehlers-Danlos syndrome, a connective tissue condition that makes joints unusually flexible.
What the conventional approach to POTS looks like
The standard path is thoughtful and often helpful. A cardiologist or autonomic specialist rules out other causes and usually confirms POTS with a tilt-table test or an active stand test. Care then focuses on managing symptoms:
- More fluids and salt to increase blood volume
- Compression garments to reduce blood pooling in the legs
- A gradual, often recumbent exercise program
- Medications that slow heart rate or support blood pressure
For many people, these steps make daily life noticeably easier. They are worth doing, and nothing in this article is a reason to stop them.
Why POTS can be so hard to pin down
POTS usually takes a long time to diagnose. In a survey of nearly 5,000 people with POTS, the median time from first symptoms to diagnosis was two years. Along the way, many people are told their symptoms are anxiety, deconditioning, or “all in their head.”
Part of the reason is that the routine tests most people get, such as bloodwork, an EKG, and even brain imaging, are designed to find structural damage or disease. They are not designed to measure how well your brain processes balance and posture information in real time. So the results come back normal, even though you clearly do not feel normal.
A different question: what is the brain responding to?
Most POTS care asks how to manage the heart rate. We also ask a different question: why is the nervous system overreacting to something as ordinary as standing up?
Your gravity sensors
Deep in each inner ear are the otoliths. They sense linear motion and, most importantly, gravity. They are the main way your brain knows which way is up and whether your body is moving toward the ground.
Research has shown that otolith signals help trigger the blood vessel tightening your body needs when you stand. Scientists call this the vestibulosympathetic reflex. A 2026 study of people with POTS found differences in otolith function compared with healthy people, and those differences were linked to stronger fight-or-flight output. That study shows an association, not proof of cause, but it points in a meaningful direction.
What we see in our testing
In our clinical model, the problem is often a calibration mismatch. You have balance sensors on both sides, and they are supposed to agree. When the left and right sides are out of balance with each other, they send conflicting information to the brainstem and cerebellum, and from there to the parts of the brain that build your sense of where your body is in space.
We believe that mismatch may do two things at once. It may give the brain a false picture of your position, and it may weaken the brain’s normal brake on the fight-or-flight system. Without that brake, standing up can set off an exaggerated stress response: a racing heart, shakiness, and the feeling that something is wrong.
This part is clinical observation rather than settled research. It reflects patterns we see repeatedly in our testing, and the published science is still catching up.
Where the neck comes in
When the brain gets unreliable balance information, the body tends to protect itself by bracing. Over time, posture does not just lean. It twists and compresses, a bit like a soda can being squeezed. In some people that compression concentrates at the top of the neck, right where the brainstem sits. In our experience, that can add another layer of interference between the body and the brain.
How we look at what may be driving your POTS
We do not diagnose POTS, and we do not do tilt-table testing. Your cardiologist or medical doctor handles diagnosis. What we measure is how your brain is handling balance and posture:
- Eye movement testing with video goggles, including in complete darkness, which shows how the balance system and brainstem are working
- A balance platform that shows how steady you are when your eyes, feet, or both are challenged
- Posture measurements that show how your body is twisting, tilting, and shifting weight
Depending on when your symptoms are strongest, we may test you seated or lying down. The goal is to find where the biggest mismatch is, so care can start there.
When to see a doctor first
Some symptoms need medical attention before anything else. See your doctor or seek emergency care if you have:
- Fainting that causes an injury
- Fainting during exercise
- Chest pain or pressure
- A racing heart that does not settle when you lie down
- POTS-like symptoms with no diagnosis yet
What the research says
The research on POTS is growing quickly. Expert consensus statements describe POTS as a real, often disabling condition with several possible underlying causes. Studies have confirmed that the inner ear’s gravity sensors help regulate blood pressure when you stand, and early research suggests otolith function may differ in people with POTS. What has not yet been studied directly is whether retraining the balance system improves POTS symptoms over time. Our approach is based on that underlying physiology and on what we observe in practice, and we say so plainly.
What this does and does not claim
We are not claiming that the balance system is the cause of every case of POTS, or that our care replaces your medical team. POTS has several recognized subtypes and contributing factors. We are suggesting that, for some people, the way the brain processes gravity and posture may be part of the picture, and that it can be measured.
Where to go from here
If you are wondering what kind of provider can help with this side of POTS, our guide to choosing a POTS specialist in the Denver area walks through what to look for. And if you want an honest answer about recovery, read whether POTS goes away.
You can also learn more about our approach to POTS and dysautonomia care in Denver, or see how the Omega Method works. We see patients from Wheat Ridge, Denver, Arvada, Lakewood, Golden, Littleton, and surrounding Colorado communities.
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References
- Sheldon RS, Grubb BP, Olshansky B, et al. 2015 Heart Rhythm Society expert consensus statement on the diagnosis and treatment of postural tachycardia syndrome, inappropriate sinus tachycardia, and vasovagal syncope. Heart Rhythm. 2015;12(6):e41-e63.
- Vernino S, Bourne KM, Stiles LE, et al. Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting, Part 1. Autonomic Neuroscience. 2021;235:102828.
- Shaw BH, Stiles LE, Bourne K, et al. The face of postural tachycardia syndrome: insights from a large cross-sectional online community-based survey. Journal of Internal Medicine. 2019;286(4):438-448.
- Yates BJ, Bolton PS, Macefield VG. Vestibulo-sympathetic responses. Comprehensive Physiology. 2014;4(2):851-887.
- Woo T, Kim Y, Kim J, et al. Vestibulo-sympathetic interaction and otolith function in postural orthostatic tachycardia syndrome. Clinical Autonomic Research. 2026;36(1):89-101.
- Miller AJ, Stiles LE, Sheehan T, et al. Prevalence of hypermobile Ehlers-Danlos syndrome in postural orthostatic tachycardia syndrome. Autonomic Neuroscience. 2020;224:102637.
