What POTS actually is.
POTS is a disorder of orthostatic intolerance — difficulty tolerating the upright position. When a person with POTS stands, too little blood returns to the heart, and the heart speeds up sharply to compensate. That compensation is where the name comes from: postural (related to position), orthostatic (related to standing), tachycardia (fast heart rate).
Clinicians use specific criteria. The Heart Rhythm Society's expert consensus defines POTS as a sustained heart-rate increase of at least 30 beats per minute when moving from lying down to standing — at least 40 beats per minute for adolescents ages 12 to 19 — together with frequent standing-related symptoms, and without the significant blood-pressure drop called orthostatic hypotension.
Notice that the heart-rate number alone is not the diagnosis. The symptoms, the pattern over time, and the exclusion of other causes matter just as much, which is why POTS is confirmed by a clinician rather than by a single measurement.
How POTS tends to show up.
The most recognizable pattern is symptoms that arrive with standing and ease when you lie back down: lightheadedness or dizziness, a racing or pounding heart, sometimes fainting or near-fainting. Many people also describe fatigue, shortness of breath, exercise intolerance, and the thinking difficulty often called brain fog.
POTS is more common in women, and NINDS notes it mainly affects people between the ages of 15 and 50. Symptoms can wax and wane over time rather than holding steady.
One honest caution: every symptom on this list also belongs to other conditions, from anemia and thyroid problems to dehydration, medication effects, anxiety, and heart-rhythm disorders. Recognizing yourself in these patterns is a reason to be evaluated, not a diagnosis.
Why POTS happens — and what's still uncertain.
There is no single cause of POTS, and researchers are candid about how much remains unsettled. What is well described is when it tends to start: NINDS notes that POTS often begins after a viral illness, a pregnancy, major surgery, or physical trauma.
Several mechanisms have been documented, and they can coexist in the same person. The Heart Rhythm Society consensus reports that blood volume is reduced in up to 70 percent of patients — one reason fluid status gets so much attention in POTS care — and that up to half show a restricted autonomic neuropathy, meaning trouble in the small nerve fibers that regulate blood vessels.
Two more threads are under active study. Some research groups are investigating autoimmune features in POTS, including overlap with recognized autoimmune conditions. And some patients have symptoms that overlap with mast cell activation syndrome, an allergy-adjacent disorder with its own testing pathway. None of these threads explains every case, which is exactly why a careful, individualized evaluation matters more than any single theory.
We keep separate guides on three of these threads — autoimmunity, fluid volume, and mast cell activation — linked at the end of this page.
How clinicians evaluate possible POTS.
The consensus-recommended starting point is unglamorous and thorough: a complete history and physical examination, orthostatic vital signs — heart rate and blood pressure measured lying down and then standing — and a 12-lead ECG. Depending on what those show, a clinician may add blood work, thyroid studies, tilt-table testing, autonomic testing, or an echocardiogram.
You may have seen instructions online for checking your own pulse while lying down and after standing. Writing down what you notice at home can be genuinely useful to bring to an appointment — but a home check cannot diagnose POTS. Measurement technique matters, the criteria require sustained readings under controlled conditions, and the diagnosis also depends on ruling out other causes. If you feel faint during any standing measurement, sit or lie down immediately; do not push through it.
A similar caution applies to salt and fluids. The consensus statement describes increased daily fluid and dietary salt for some patients, if tolerated — but the amounts are individualized, and extra salt or aggressive fluid loading can be the wrong move for people with high blood pressure, kidney disease, or heart conditions. Talk with a clinician before changing your salt or fluid intake; this is a decision to make with supervision, not from a webpage.
When other care needs to come first.
Some symptoms need urgent medical evaluation before any conversation about POTS: fainting that causes injury, fainting during exercise, chest pain, severe shortness of breath, or passing out with a family history of sudden cardiac death. If any of these is happening now, call 911 or go to the nearest emergency room. If they have happened recently, tell your primary care provider or a cardiologist promptly.
Care at Gates Brain Health is complementary functional neurology. It does not replace your primary care provider or cardiologist, and decisions about medications stay with the clinicians who prescribe them. Many people exploring this practice have already seen other specialists; care here is designed to work alongside those relationships, not instead of them.
Questions worth asking when you call.
The practice's published focus includes POTS among the chronic neurological conditions it works with, and its POTS material describes attention to fluid volume, autoimmune screening, small-fiber nerve function, and mast cell activation as threads a thorough evaluation can explore. What the examination itself involves is described on the treatment page — we won't repeat it here.
If you are considering a call to (775) 507-2000, these questions can make the conversation more useful:
- Does an evaluation here make sense given what my cardiologist or primary care provider has already found?
- What does the examination involve, and how long should I plan for?
- How does Dr. Gates approach POTS alongside the specialists I already see?
- Which records should I bring — tilt-table results, ECGs, recent labs?
- What does the free consultation cover before I commit to anything?