How POTS Is Diagnosed
Most pages explaining how POTS is diagnosed describe the test. If you are reading this, there is a good chance the tests already happened and came back normal, or nobody ordered them. This page covers what a diagnosis actually requires, and what to do when the appointment did not produce a desired outcome.
The criteria, in plain terms
POTS has a published definition, The Canadian Cardiovascular Society position statement sets four conditions, and all four have to hold.1
| Condition | What it means |
|---|---|
| Heart-rate rise on standing | An increase of at least 30 beats per minute that is still present after 10 minutes of standing. At least 40 beats for ages 12 to 19. The rise has to be sustained, so the diagnosis is not made before the 10 minute mark. |
| Blood pressure holds | No orthostatic hypotension. Systolic must not fall more than 20 mmHg, diastolic not more than 10 mmHg, within 3 minutes. A steep blood pressure drop points somewhere else. |
| Duration | Symptoms present for at least 3 months. POTS is a chronic pattern, not a bad week. |
| Other causes excluded | Dehydration, anemia, thyroid disease, medication effects, deconditioning and others ruled out. |
The last row is the one turning a number into a diagnosis. A pulse climbing 35 beats on standing is a finding. Whether it is POTS depends entirely on what else has been ruled out, which is why a single measurement never settles it.
The heart rate timing in the first row is worth reading twice, because it is often the people get wrong. The rise must be sustained. A heart rate that jumps 40 beats two minutes after standing and settles back before the ten minute mark does not meet the criterion, which is why a test ending early cannot confirm or exclude anything.
Missing the threshold does not mean nothing is wrongYou can be genuinely orthostatic, lightheaded and tachycardic whenever you are upright, and still not meet the POTS definition. The criteria mark the boundary of one named syndrome. They are not a ruling on whether your body is coping with standing. Orthostatic intolerance is worth treating on its own terms, so a negative result is a reason to ask what else is going on rather than a reason to stop.
What the testing involves
Confirmation usually comes from a tilt table test. The table tilts from lying to near-upright, and you are secured to it while heart rate and blood pressure are recorded continuously. It sounds dramatic and its uneventful, and it exists because the abnormality only appears when the body is upright.
An Active Stand Test does the same job without the table. You lie down, then stand, and readings are taken at set intervals. In the 2025 study of highly symptomatic Long COVID patients, everyone with clinically suspected POTS went on to a cardiologist evaluation with a 48-hour ECG, head-up tilt testing and an Active Stand Test.2
Because confirming the pattern and measuring its reach are two different jobs, autonomic function testing and the COMPASS 31 assessment exist to do the second one, showing how far the dysfunction extends rather than only whether it is present.
Heart rate variability measures the variation in time between heartbeats rather than the heart rate itself. In dysautonomia, reduced variability reflects raised sympathetic and lowered parasympathetic activity. The metrics you will see named are SDNN for overall variability, RMSSD and pNN50 for parasympathetic activity, and the LF to HF ratio for overall balance. An autonomic problem is suggested when at least two of six parameters are abnormal.
If you track HRV on a wearable, two things matter more than the number on any given morning. The trend over one to two weeks is what carries information; a single reading carries almost none. And HRV cannot be compared across devices or across different measurement windows. Your figure and someone else’s are not the same measurement, even when they share a name. Track against your own baseline and bring the trend, not a screenshot of one day.
Why your tests come back normal
The autonomic nervous system is not directly measurable on a standard blood panel or on routine imaging. Nervous system tests assess structure. This is a problem of regulation, and the two need different instruments.
An echocardiogram, a resting ECG and routine bloodwork can all be entirely normal in someone with textbook POTS. Those results are accurate. They answer the question about structure, while the abnormality only shows itself when you are upright and somebody is measuring.
If you have been told your tests are normal, the tests were probably normal. That is a statement about what was measured, not about whether something is wrong with you.
Why symptoms alone are not the answer
This finding should change how POTS is approached after COVID, and it is almost never mentioned on pages about diagnosis.
Researchers compared symptoms across three groups in the 2025 cohort: confirmed POTS, tested and negative, and no clinical signs of POTS at all. The distribution of symptoms showed no significant differences between the three groups.2
If a symptom questionnaire cannot rule POTS in, and cannot rule it out either, then no amount of describing how you feel will settle the question. It cuts both ways. People get missed, and people get told they must have POTS when they do not. This is why an objective measurement across a position change separates them.
Why it takes so long
A survey of 4,835 POTS patients found a median of 24 months between first raising the symptoms with a physician and receiving the diagnosis.3 The same paper records the delay is improving, which is worth saying because most pages quoting this figure leave this part out.
The delay is mostly a measurement problem. The criteria requires a number the seated appointment do not produce, and the tests ordered first are built to answer a different question.
Checking at home before your appointment
When you can bring evidence rather than a description, it can help change the conversation. It also carries a real risk, so the safety framing below is not a formality.
Read this before you trying, people with orthostatic intolerance can faint so precautions need to be taken. Standing still is the activity this test is designed to provoke, so treat it accordingly.
Have someone with you. Stand with your back against a wall, close enough to a chair or a bed that you can reach it, so there is something behind you and somewhere to get down to. If you feel lightheaded, graying out, sweaty or nauseated, sit or lie down immediately and stop. Do not do this alone, and do not repeat it to get a better number.
If you have fainted before, or you have any heart condition, ask your clinician how to do an at-home evaluation safely rather than starting on your own.
With those conditions met, lie down and rest a few minutes, then take your pulse and blood pressure. Stand up, and take both again shortly after standing, then keep going and take a reading at the ten minute mark, because the last reading is the criteria defining POTS.1 Write the numbers down with the time of day.
Note what preceded. Heat, a hot shower, standing in a queue, a missed meal, poor sleep, stress, or where you are in your cycle.
A week of position-paired numbers alongside triggers is more useful than trying to describe how you have been feeling, and it is considerably harder for an appointment to wave away.
Someone with you, your back to a wall, and somewhere to get down to within reach, every time you repeat it.
The risk does not drop because you did it yesterday without trouble.
What you measure at home is a reason to book an evaluation. It is not a diagnosis. A normal result on one morning does not rule POTS out, and a high number on another does not rule it in, because the criteria also require other causes to be excluded and that is not something you can do at your kitchen table.
Looking for the cause
Confirming POTS is only half the workup. Next steps include, what is driving the symptoms, and looking at secondary causes.
A secondary-cause workup should include thyroid function, vitamin B12 and thiamine, autoimmune markers, and a review of current medications. B12 and thiamine deficiency can each produce autonomic dysfunction and both are correctable once somebody thinks to check.
Medications also belong on the secondary-cause workup list. Certain antidepressants, particularly TCAs and SNRIs, increase sympathetic activity and reduce vagal tone, so if your symptoms worsened after a medication change, that sequence is worth raising with whoever prescribed it.
The dominant mechanism also shapes treatment, which is covered on types of POTS.
What to ask for
Three requests move an appointment better than describing symptoms.
Ask for heart rate and blood pressure to be recorded across a change in position, not seated only.
Ask whether the workup will look for a secondary cause, or only confirm the diagnosis.
When a treatment is proposed, find out the target, the heart rate or the autonomic dysfunction underneath it.
If you are still working out which kind of clinician to approach, that has its own page: what type of doctor treats POTS.
Getting evaluated
Evaluation here starts with your history, moves through testing built for the autonomic system rather than around it, and works toward which mechanism is actually driving your symptoms. For what POTS is and how it is treated overall, see POTS specialist and treatment, and for the wider condition it sits inside, see dysautonomia specialist and treatment.
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Frequently asked questions
Can POTS show up in bloodwork?
No. The autonomic nervous system is not directly measurable on a standard blood panel, and there is no diagnostic blood test for POTS. Bloodwork still matters, but for a different reason: it excludes other causes, a required step before POTS can be confirmed. Thyroid function, vitamin B12, thiamine and autoimmune markers all belong in that workup. POTS itself is identified by what heart rate and blood pressure do across a change in position.
What test confirms POTS?
A tilt table test is the usual confirmation. The table tilts from lying to near-upright, and you are secured to it while heart rate and blood pressure are recorded continuously. An Active Stand Test measures the same response without the table. Either way the diagnosis requires a heart-rate rise of at least 30 beats per minute that is still present at 10 minutes of standing, 40 beats for ages 12 to 19, without a significant drop in blood pressure, with symptoms lasting at least three months and other causes excluded. The rise has to be sustained, so the diagnosis is not made before the 10 minute mark.
Can I diagnose POTS at home?
No. You can recognize a pattern worth investigating, which is a different and still useful thing. Measuring your pulse and blood pressure lying down and then standing can show whether the rise is there, but a diagnosis also requires other causes to be excluded and that cannot be done at home. Standing tests are designed to provoke the symptom, so anyone attempting one should have somebody present and should sit or lie down immediately if they feel faint.
Why were my tests normal if I have POTS?
Standard cardiac tests are usually performed lying down or sitting, and POTS is defined by what happens when you stand. A resting ECG, an echocardiogram and routine bloodwork can all be normal in someone with clear POTS. The autonomic nervous system is also not directly measurable on those tests. They assess structure, and this is a problem of regulation.
How long does it take to get diagnosed with POTS?
Longer than it should. A survey of 4,835 patients found a median of 24 months between first raising the symptoms with a physician and receiving the diagnosis, with the slowest quarter waiting six years or more. The same paper records that the delay is improving. The wait is largely a measurement problem, because the criteria require a reading across a position change a seated appointment does not produce.
Does heart rate variability diagnose POTS?
No. HRV measures the variation in time between heartbeats and gives useful information about autonomic balance, but it does not confirm or exclude POTS on its own. Two cautions matter if you track it on a wearable. The trend over one to two weeks carries the information, not any single morning’s reading. And HRV cannot be compared across different devices or measurement windows, so your number and someone else’s are not the same measurement.
References
- Raj SR, Guzman JC, Harvey P, Richer L, Schondorf R, Seifer C, Thibodeau-Jarry N, Sheldon RS. Canadian Cardiovascular Society Position Statement on Postural Orthostatic Tachycardia Syndrome (POTS) and Related Disorders of Chronic Orthostatic Intolerance. Can J Cardiol. 2020 Mar;36(3):357-372. doi:10.1016/j.cjca.2019.12.024. PMID 32145864.
- Björnson M, Wijnbladh K, Törnberg A, Svensson-Raskh A, Svensson A, Ståhlberg M, Runold M, Fedorowski A, Nygren-Bonnier M, Bruchfeld J. Prevalence and Clinical Impact of Postural Orthostatic Tachycardia Syndrome in Highly Symptomatic Long COVID. Circ Arrhythm Electrophysiol. 2025 Oct;18(10):e013629. doi:10.1161/CIRCEP.124.013629. PMID 41025260.
- Shaw BH, Stiles LE, Bourne K, Green EA, Shibao CA, Okamoto LE, Garland EM, Gamboa A, Diedrich A, Raj V, Sheldon RS, Biaggioni I, Robertson D, Raj SR. The face of postural tachycardia syndrome – insights from a large cross-sectional online community-based survey. J Intern Med. 2019 Oct;286(4):438-448. doi:10.1111/joim.12895. PMID 30861229.
This page is for education and does not constitute medical advice, diagnosis, or a treatment recommendation for any individual. The self-measurement described here is a way of recognizing a pattern worth investigating and is not a diagnosis. Do not start, stop or change any treatment based on this page. Speak with a qualified clinician about your own situation. If you have chest pain, fainting, or a heart rate that will not settle, seek urgent medical care.