Postural Orthostatic Tachycardia Syndrome (POTS)

A form of dysautonomia with major overlap

Last reviewed: October 2026 · 29 sources

Educational only, not medical advice. This page shares general information and community experience. It isn’t a diagnosis or a treatment plan. Please talk with your doctor or another licensed healthcare provider before starting, stopping, or changing any test, supplement, medication, or treatment.

At a glance

  • What it is: a disorder of the autonomic nervous system (the “automatic” system that controls heart rate and blood pressure). When you stand up, your heart rate rises too much and you feel lightheaded and unwell [1, 2].
  • How it’s defined: a heart rate rise of at least 30 beats per minute within 10 minutes of standing (at least 40 in ages 12–19), without a big drop in blood pressure, plus symptoms for at least 3 months [2, 3].
  • It’s real and recognized, but often missed. In a large survey, the median wait for diagnosis was 2 years [4]. POTS is not caused by anxiety [1].
  • Management: usually starts with fluids, salt (with your doctor’s guidance), compression, a gradual exercise plan and avoiding triggers, with medicines added if needed [2, 3].

Many people with POTS spend years being told they’re anxious, out of shape, or just “fine” because their resting tests look normal. POTS is a recognized medical condition with published diagnostic criteria [2, 3]. This page explains how it’s defined, how it’s diagnosed and what management usually looks like.

What POTS is

POTS is a common disorder of the autonomic nervous system. It is defined by an excessive heart rate increase and symptoms like lightheadedness when you stand up [1]. It’s a “syndrome,” meaning a cluster of symptoms that have many possible underlying causes, rather than a single disease [1, 5].

The definitions. Major expert groups use very similar criteria:

  • Heart Rhythm Society (HRS), 2015: frequent symptoms with standing; a heart rate increase of 30 bpm or more when moving from lying down to standing (40 bpm or more for ages 12–19); and no orthostatic hypotension (a drop in systolic blood pressure of more than 20 mm Hg) [2].
  • 2019 NIH expert consensus (published 2021): the same heart rate rise within 10 minutes of standing or head-up tilt, symptoms for at least 3 months, and no other condition that better explains the fast heart rate [3].
  • Canadian Cardiovascular Society (CCS), 2020: stresses that the diagnosis needs both the heart rate rise and typical symptoms that are worse upright and better lying down. It warns against labelling people with POTS when they don’t meet the criteria [5].
  • Dysautonomia International also accepts a heart rate over 120 bpm within 10 minutes of standing [1].

Who gets it. HRS estimates that about 0.2% of people have POTS. Most patients first present between ages 15 and 25, and more than 75% are female [2]. The NIH consensus estimates 0.2–1% of the U.S. population (roughly 1–3 million people), while noting this hasn’t been properly studied [3]. Dysautonomia International says experts estimate the number may have doubled since the COVID-19 pandemic [1].

Common symptoms

In a survey of 4,835 people diagnosed with POTS, the most common symptoms were lightheadedness (99%), racing heart (97%), feeling about to faint (94%), headache (94%) and trouble concentrating (94%) [4]. Other symptoms include:

  • Fatigue, exercise intolerance, shakiness and generalized weakness [1, 2]
  • Blurred vision [2]
  • Nausea and other gut symptoms [1, 3]
  • Chest pain and shortness of breath [1]
  • Fainting [1]
  • Cold or painful hands and feet, and a reddish-purple color in the legs when standing that fades when you lie down [1]

Symptoms can be made worse by heat, meals and over-exertion [3]. Some people can keep working and studying; for others, everyday tasks like showering or standing in line are hard [1]. Dysautonomia International estimates that about 25% of people with POTS are unable to work [1].

Not anxiety. Some POTS symptoms, like a racing heart, overlap with anxiety, and people with POTS are often misdiagnosed with anxiety or panic disorder. Dysautonomia International notes research showing people with POTS are no more likely to have anxiety than the general public [1].

Causes and risk factors

POTS can have several underlying mechanisms, and often no single cause is found [1, 5]. Researchers describe overlapping types, including POTS with low blood volume, POTS linked with a partial autonomic neuropathy (about half of patients have small-fiber nerve involvement) and “hyperadrenergic” POTS with high norepinephrine levels. Many people show features of more than one [1].

Conditions and events linked with POTS include [1]:

  • Viral and other infections (for example mononucleosis/Epstein-Barr virus, Lyme disease)
  • Autoimmune diseases
  • Ehlers-Danlos syndromes and joint hypermobility
  • Mast cell activation disorders
  • Pregnancy, surgery or trauma
  • Deconditioning, diabetes, vitamin deficiencies and anemia

Autoimmunity research. One study found raised levels of certain autoantibodies, mostly against the alpha-1 adrenergic receptor, in 89% of 55 POTS patients. It supports, but doesn’t prove, the idea that some POTS is autoimmune [6].

Mold. A few small studies, mostly from one Finnish research group, reported more autonomic symptoms in people exposed to damp buildings [7, 8, 9]. Other researchers have criticized earlier work from this group [10], and mold isn’t on Dysautonomia International’s list of known associated conditions [1]. This is an association worth more research, not a proven cause.

How POTS is diagnosed

  • Active stand test. Heart rate and blood pressure are measured lying down and then after standing, typically at 2, 5 and 10 minutes [1]. The NIH consensus says a 10-minute standing test can usually identify POTS [3]. Because a single test can miss POTS, Dysautonomia International cautions against ruling it out on one normal result if symptoms fit [1].
  • Tilt table test. You’re strapped to a table that tilts upright while you’re monitored. It is useful when fainting conditions or nerve problems are suspected, or when someone can’t stand for 10 minutes [3].
  • Ruling out look-alikes. Before diagnosing POTS, clinicians should look for other causes of a fast heart rate, such as dehydration, anemia, fever, pain, infection, an overactive thyroid, certain medicines, primary anxiety disorders or eating disorders [3].
  • Other autonomic tests like sweat tests or skin biopsies for small-fiber nerves may be done in specialist clinics [1].

Who diagnoses it? Cardiologists (especially electrophysiologists), neurologists who specialize in autonomic disorders, and some primary care doctors. Dysautonomia International recommends seeing a physician who has experience with autonomic disorders [1].

Treatment approaches to discuss with your clinician

There’s no cure yet, and there are no FDA-approved medicines specifically for POTS. The NIH consensus notes that evidence for many medicines used is not robust [3]. Management is usually a combination of approaches, tailored to you.

Non-medication approaches (usually first):

  • Stopping medicines that make POTS worse, where appropriate, with your prescriber’s input. HRS specifically advises against drugs that block the norepinephrine transporter [2, 3].
  • More fluids. Many POTS experts suggest drinking more fluid, often 2–3 liters a day [2, 3]. Some guidelines, like the Canadian position statement, say at least 3 liters [11]. Ask your doctor what’s right for you.
  • More salt, with your doctor’s guidance. Guidelines often suggest extra salt, but it isn’t right for everyone. It can raise blood pressure and cause swelling, so your clinician should set your target [3, 11]. Dysautonomia International points out that salt only helps when you also increase fluids [12].
  • Compression. Waist-high compression, especially over the abdomen and legs, reduced heart rate and symptoms during tilt testing in a 30-person trial [3, 13].
  • A gradual exercise program. HRS says a regular, structured, progressive program can help. It should start with exercise that doesn’t require being upright, such as rowing machines, recumbent bikes and swimming [2]. The NIH consensus warns that you may feel worse for up to 6 weeks before you feel better [3].
  • Raising the head of the bed and a healthy diet are also among common strategies [1].

Medicines your clinician may consider. Options sometimes used include fludrocortisone, midodrine, pyridostigmine, propranolol or other beta-blockers, ivabradine, and clonidine or methyldopa. The choice depends on the type of POTS and your other conditions [2, 3]. Each has side effects and precautions, so these are always prescribed decisions, not something to start on your own. If you also have mast cell symptoms, beta-blockers need extra caution [14].

Treat underlying causes when they can be found. Dysautonomia International stresses this as an important part of care [1].

Living with POTS: practical day-to-day help

  • Learn your early warning signs. Before fainting, people may feel weak, sweaty or sick, or notice tunnel vision. Getting up slowly and avoiding situations you know set you off can help. If you’ve never fainted before, faint often, or have new symptoms with fainting, see your provider [15].
  • Watch for triggers like heat, large meals, long standing and over-exertion, and plan around them where you can [3].
  • Pace yourself. Build activity gradually rather than pushing through on good days and crashing afterward [2, 3].
  • Ask about accommodations at school or work, such as seating, water access and flexible schedules. POTS can limit daily function as much as some heart and lung conditions [1].
  • Hope for improvement. In a Mayo Clinic follow-up of patients whose POTS began in adolescence, 18.2% reported their symptoms had resolved and 52.8% reported improvement, about 5 years after diagnosis [1].
  • See our POTS daily management tips and Trifecta reference.

How POTS overlaps with the other conditions

  • hEDS. In one study of 91 people with POTS, 31% met the 2017 hEDS criteria and another 24% had generalized joint hypermobility [16]. Autonomic problems are frequently seen in hEDS [17].
  • MCAS. In one clinic study, 42% of POTS patients had extra symptoms plus at least one lab marker suggesting mast cell activation [18]. Rates vary hugely depending on the MCAS criteria used [19]. A 2020 review found the evidence for a true hEDS-POTS-MCAS link to be weak [20].
  • Mold toxicity and CIRS. Small studies suggest an association between damp buildings and autonomic symptoms, but cause and effect hasn’t been shown [7, 10]. CIRS practitioners describe low blood volume in some CIRS patients [21].

What’s known and what’s debated

Generally accepted: POTS has clear published criteria; it’s not caused by anxiety; fluids, salt with medical guidance, compression and gradual exercise are standard first steps [1, 2, 3].

Still being researched:

  • The underlying causes, including autoimmunity [3, 6].
  • How well individual medicines work. Evidence is limited and none are FDA-approved for POTS [3].
  • The best salt and fluid targets. The NIH consensus says more research is needed on the true benefit and best amount of salt [3].
  • How strongly POTS is linked with MCAS, hEDS and mold exposure [10, 19, 20].

Functional & integrative perspective · evidence varies

The functional and integrative perspective

How functional and integrative practitioners see POTS

POTS itself is a recognized diagnosis [2]. Functional and integrative practitioners often look for an underlying driver, and Dysautonomia International lists autoimmune, mast cell and connective tissue conditions among those linked with POTS [1]. The models below are hypotheses.

  • Autoimmunity. One study found raised autoantibodies in 89% of 55 POTS patients, which supports but doesn’t prove an autoimmune role [6]. A 2021 expert review notes that autoantibody tests are often positive but often non-specific [3]. The first randomized trial of IVIG (an immune therapy) for presumed autoimmune POTS, with 30 patients, found no difference compared with albumin infusions [25]. Evidence: mixed; one small negative trial.
  • Mast cells. Dr. Lawrence Afrin writes that POTS, especially the hyperadrenergic type, has been associated with MCAS, and suggests checking for MCAS when other mast cell symptoms are present [26]. One clinic study found mast cell markers in 42% of POTS patients [18], but rates vary widely with the criteria used [19], and the 2021 review says accurate data aren’t available [3]. Evidence: associations. See the MCAS perspective, including a beta-blocker caution [14].
  • The hEDS and MCAS “triad.” A 2018 review notes that EDS and POTS frequently coexist and suggests mast cell problems may form a distinct subgroup, calling for larger studies [27]. A 2020 review found the evidence for a true three-way link weak [20]. See hEDS. Evidence: small studies and reviews.
  • Mold and toxins. ISEAI’s view is noted under recommendations below. A few small Finnish studies support an association [7, 8, 9], but others have criticized that work [10]. See the mold toxicity perspective. Evidence: association only.

What functional and integrative practitioners often recommend

Most practical POTS measures, such as fluids, salt, compression and exercise, are already mainstream care; see treatment approaches and day-to-day help above. Functional and integrative clinicians often add a search for underlying drivers. Evidence for these extras is thin, and most have not been tested in controlled trials. This is not medical advice. Please talk with a licensed clinician before trying any of them.

  • Looking for a “root cause.” ISEAI lists POTS among illnesses it thinks “may be caused or exacerbated by” environmental toxins [23]. Dysautonomia International also stresses treating underlying causes, such as autoimmune disease, mast cell disorders, infections and vitamin deficiencies [1]. Evidence: mainly associations and expert opinion. Mold is not on Dysautonomia International’s list [1].
  • Gut health and diet. A dietitians’ review notes that gut symptoms are common in POTS. One study found celiac disease in 4% of patients, so the review advises screening before cutting out gluten. It also notes that restrictive diets can cause nutrient deficiencies and advises against unnecessary restriction [11]. Evidence: small studies and expert review.
  • Nutrient approaches. The same review says correcting deficiencies such as iron or B12 is important, ideally after testing [11]. One case report from a UC San Diego team described a woman who improved on methylated B vitamins after standard treatment failed [24]. Evidence: a single case report; not tested in trials.

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What to do next

General information, not a diagnosis or a treatment plan. A licensed clinician can tell you which of these steps fit you.

  1. Step 1Start this week

    • Note when symptoms happen, especially after standing up, since POTS symptoms often appear on standing [28].
    • Note triggers such as heat, large meals, long standing and over-exertion [3]. AHRQ suggests writing down all your questions and concerns before a visit [29].
    • Our symptom checklist can help you organize what you notice.

  2. Step 2Choose who to see

    • Start with your primary care doctor: NINDS suggests discussing your concerns with a healthcare provider if you suspect POTS [28].
    • Because POTS can look like other conditions, people may need specialists such as cardiologists or neurologists [28]. Dysautonomia International recommends a physician with experience treating autonomic disorders [1].
    • See also the provider directories on our homepage.

  3. Step 3Tests to ask about

    • Ask about an active stand test, with heart rate and blood pressure measured lying down and then standing [1, 3].
    • A tilt table test is useful when fainting conditions or nerve problems are suspected, or when someone can’t stand long enough for the stand test [3].
    • Ask about ruling out look-alikes such as dehydration, anemia or an overactive thyroid [3]. One normal stand test doesn’t rule out POTS if your symptoms fit, Dysautonomia International cautions [1].

  4. Step 4Everyday steps mainstream sources support

    • Ask your doctor about more fluids, extra salt, compression garments and a gradual exercise program, which guidelines list among first steps [2, 3, 13].
    • Get your own amounts from your doctor, because extra salt isn’t right for everyone and can raise blood pressure [3, 11]; NINDS also notes graduated exercise isn’t recommended for everyone [28].
    • Don’t start or stop medicines on your own, since some can worsen POTS [28].

  5. Step 5Prepare for the appointment

    • Bring a list of all the medicines you take [29]. Our Doctor visit prep sheet has space for your stand-test readings and past results.
    • People with POTS are often misdiagnosed with anxiety, but their symptoms are real [1]. If you feel dismissed, consider a second opinion: AHRQ says wanting one “is not pushy or rude” and suggests asking for a doctor who doesn’t work in the same office [29].
    • Dysautonomia International is a patient organization with POTS information [1].
    • Then use the Questions to ask your doctor below.

  6. Step 6When to get urgent care

    • Call 911 if someone faints and doesn’t become alert within a couple of minutes, is injured, or has chest pain or a pounding or irregular heartbeat [15], or for sudden crushing chest pressure [22].
    • See the full list under When to get urgent help.

Questions to ask your doctor

  • Can we do an active stand test (lying, then standing for 10 minutes), or do I need a tilt test?
  • What else should we rule out?
  • How much fluid and salt is right for me, given my blood pressure, heart and kidneys?
  • What kind of compression should I try?
  • What exercise plan is safe for me to start, and how should I build up?
  • If we try a medicine, what are we aiming for and which side effects should I watch for?
  • Should I see an autonomic specialist?

When to get urgent help

Call 911 or your local emergency number if someone faints and doesn’t become alert within a couple of minutes, is injured or bleeding, is pregnant, or has chest pain, a pounding or irregular heartbeat, loss of speech, vision problems, inability to move a limb, or a seizure [15]. Also call for sudden crushing chest pressure or chest pain with shortness of breath [22].

Sources

Numbers in brackets in the text link to these sources. Links were checked in October 2026. Some sources are written by people who support a particular approach; we've tried to say so in the text.

  1. Dysautonomia International. Postural Orthostatic Tachycardia Syndrome. Web page, accessed October 10, 2026. https://www.dysautonomiainternational.org/page.php?ID=30
  2. 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:e41-e63. PMID: 25980576. https://pmc.ncbi.nlm.nih.gov/articles/PMC5267948/
  3. 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. Auton Neurosci. 2021;235:102828. PMID: 34144933. https://pmc.ncbi.nlm.nih.gov/articles/PMC8455420/
  4. Shaw BH, Stiles LE, Bourne K, et al. The face of postural tachycardia syndrome - insights from a large cross-sectional online community-based survey. J Intern Med. 2019;286(4):438-448. PMID: 30861229. https://pmc.ncbi.nlm.nih.gov/articles/PMC6790699/
  5. Raj SR, Guzman JC, Harvey P, et al. Canadian Cardiovascular Society Position Statement on Postural Orthostatic Tachycardia Syndrome (POTS) and Related Disorders of Chronic Orthostatic Intolerance. Can J Cardiol. 2020;36(3):357-372. PMID: 32145864. https://doi.org/10.1016/j.cjca.2019.12.024
  6. Gunning WT, Kvale H, Kramer PM, Karabin BL, Grubb BP. Postural Orthostatic Tachycardia Syndrome Is Associated With Elevated G-Protein Coupled Receptor Autoantibodies. J Am Heart Assoc. 2019;8(18):e013602. PMID: 31495251. https://pmc.ncbi.nlm.nih.gov/articles/PMC6818019/
  7. Hyvönen S, Lohi J, Tuuminen T. Moist and mold exposure is associated with high prevalence of neurological symptoms and MCS in a Finnish hospital workers cohort. Saf Health Work. 2020;11(2):173-177. PMID: 32596012. https://pmc.ncbi.nlm.nih.gov/articles/PMC7303478/
  8. Hyvönen S, Poussa T, Lohi J, Tuuminen T. High prevalence of neurological sequelae and multiple chemical sensitivity among occupants of a Finnish police station damaged by dampness microbiota. Arch Environ Occup Health. 2021;76(3):145-151. PMID: 32544007. https://doi.org/10.1080/19338244.2020.1781034
  9. Tuuminen T. The roles of autoimmunity and biotoxicosis in sick building syndrome as a "starting point" for irreversible dampness and mold hypersensitivity syndrome. Antibodies (Basel). 2020;9(2):26. PMID: 32580407. https://pmc.ncbi.nlm.nih.gov/articles/PMC7345570/
  10. Heinzow HS, Heinzow BGJ. Commentary: Severe sequelae to mold-related illness as demonstrated in two Finnish cohorts. Front Immunol. 2017;8:1694. PMID: 29270170. https://pmc.ncbi.nlm.nih.gov/articles/PMC5725433/
  11. Harris CI. COVID-19 Increases the Prevalence of Postural Orthostatic Tachycardia Syndrome: What Nutrition and Dietetics Practitioners Need to Know. J Acad Nutr Diet. 2022;122:1600-1605. PMID: 35697326. https://pmc.ncbi.nlm.nih.gov/articles/PMC9186518/
  12. Dysautonomia International. Please Pass the Salt (The Dysautonomia Dispatch blog). June 17, 2014. https://dysautonomiainternational.org/blog/wordpress/pleasepassthesalt/
  13. Bourne KM, Sheldon RS, Hall J, et al. Compression Garment Reduces Orthostatic Tachycardia and Symptoms in Patients With Postural Orthostatic Tachycardia Syndrome. J Am Coll Cardiol. 2021;77(3):285-296. PMID: 33478652. https://doi.org/10.1016/j.jacc.2020.11.040
  14. Shibao C, Arzubiaga C, Roberts LJ, et al. Hyperadrenergic postural tachycardia syndrome in mast cell activation disorders. Hypertension. 2005;45(3):385-390. PMID: 15710782. https://doi.org/10.1161/01.HYP.0000158259.68614.40
  15. MedlinePlus. Fainting. Web page, accessed October 10, 2026. https://medlineplus.gov/ency/article/003092.htm
  16. Miller AJ, Stiles LE, Sheehan T, et al. Prevalence of hypermobile Ehlers-Danlos syndrome in postural orthostatic tachycardia syndrome. Auton Neurosci. 2020;224:102637. PMID: 31954224. https://pmc.ncbi.nlm.nih.gov/articles/PMC7282488/
  17. Hakim A, O'Callaghan C, De Wandele I, et al. Cardiovascular autonomic dysfunction in Ehlers-Danlos syndrome-Hypermobile type. Am J Med Genet C Semin Med Genet. 2017;175(1):168-174. PMID: 28160388. https://doi.org/10.1002/ajmg.c.31543
  18. Kohno R, Cannom DS, Olshansky B, et al. Mast Cell Activation Disorder and Postural Orthostatic Tachycardia Syndrome: A Clinical Association. J Am Heart Assoc. 2021;10(17):e021002. PMID: 34398691. https://pmc.ncbi.nlm.nih.gov/articles/PMC8649306/
  19. Yao L, Subramaniam K, Raja KM, et al. Association of postural orthostatic tachycardia syndrome, hypermobility spectrum disorders, and mast cell activation syndrome in young patients; prevalence, overlap and response to therapy depends on the definition. Front Neurol. 2025;16:1513199. PMID: 40352770. https://pmc.ncbi.nlm.nih.gov/articles/PMC12063504/
  20. Kucharik AH, Chang C. The Relationship Between Hypermobile Ehlers-Danlos Syndrome (hEDS), Postural Orthostatic Tachycardia Syndrome (POTS), and Mast Cell Activation Syndrome (MCAS). Clin Rev Allergy Immunol. 2020;58(3):273-297. PMID: 31267471. https://doi.org/10.1007/s12016-019-08755-8
  21. Shoemaker R, Johnson K, Jim L, et al. Diagnostic Process for Chronic Inflammatory Response Syndrome (CIRS): A Consensus Statement. Report of the Consensus Committee of Surviving Mold. Internal Medicine Review. 2018;4(5). https://www.survivingmold.com/Publications/CIRS_diagnostic_protocol_final_5_1_2018.pdf
  22. MedlinePlus. Chest pain. Web page, accessed October 10, 2026. https://medlineplus.gov/ency/article/003079.htm
  23. International Society for Environmentally Acquired Illness (ISEAI). About EAI – Environmentally Acquired Illness. Web page, accessed October 12, 2026. https://iseai.org/about-eai/
  24. Mittal N, Portera A, Taub P. Improvement of hyperadrenergic postural orthostatic tachycardia syndrome (POTS) with methylated B vitamins in the setting of a heterozygous COMT Val158Met polymorphism. BMJ Case Rep. 2021;14(11):e245012. PMID: 34764114. https://pmc.ncbi.nlm.nih.gov/articles/PMC8586883/
  25. Vernino S, Hopkins S, Bryarly M, Hernandez RS, Salter A. Randomized controlled trial of intravenous immunoglobulin for autoimmune postural orthostatic tachycardia syndrome (iSTAND). Clin Auton Res. 2024;34(1):153-163. PMID: 38311655. https://doi.org/10.1007/s10286-024-01020-9
  26. Afrin LB. Mast cell activation disease and the modern epidemic of chronic inflammatory disease. Transl Res. 2016;174:33-59. PMID: 26850903. https://doi.org/10.1016/j.trsl.2016.01.003
  27. Bonamichi-Santos R, Yoshimi-Kanamori K, Giavina-Bianchi P, Aun MV. Association of postural tachycardia syndrome and Ehlers-Danlos syndrome with mast cell activation disorders. Immunol Allergy Clin North Am. 2018;38(3):497-504. PMID: 30007466. https://doi.org/10.1016/j.iac.2018.04.004
  28. National Institute of Neurological Disorders and Stroke (NINDS). Postural Tachycardia Syndrome (POTS). Web page, accessed October 17, 2026. https://www.ninds.nih.gov/health-information/disorders/postural-tachycardia-syndrome
  29. Agency for Healthcare Research and Quality (AHRQ). Next Steps After Your Diagnosis: Finding Information and Support (patient booklet, PDF). Accessed October 17, 2026. https://www.ahrq.gov/sites/default/files/wysiwyg/patients-consumers/diagnosis-treatment/diagnosis/diaginfo/diaginfo.pdf

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