01 · Overview
The short version
POTS is a standing-related pattern
The key clue is symptoms that start or worsen when standing and improve when lying down. A single heart-rate reading at home is not enough to explain the whole picture.
Other problems can look similar
Dehydration, anemia, thyroid disease, arrhythmias, medication effects, panic, and deconditioning can cause overlapping symptoms, so clinicians look for other causes before calling it POTS.
Daily habits often come first
Fluids, salt only when safe, compression garments, slow position changes, and gradual exercise are common first steps because they can reduce standing symptoms without making the body work harder than it can handle.
Some symptoms need urgent care
Chest pain, trouble breathing, fainting that does not quickly clear, a very irregular heartbeat, or new neurologic symptoms can point to a more serious heart or neurologic problem.
02 · Care guidance
When to get help
Emergency help
- Call 911 or local emergency services now for chest pain, severe shortness of breath, confusion, blue lips, new one-sided weakness, fainting with no quick recovery, or a very irregular heartbeat with severe symptoms.
- Seek emergency care right away if symptoms suggest shock, severe dehydration, or a dangerous heart rhythm rather than simple standing-related dizziness.
Get advice promptly
- Contact a clinician soon if you have repeated dizziness, palpitations, near-fainting, or exercise intolerance that is affecting school, work, driving, or daily life.
- Get prompt medical advice if symptoms began after an illness, after starting a new medicine, with weight loss, heavy periods, pregnancy, or signs of anemia or thyroid problems.
If symptoms are mild and stable, make a non-urgent appointment to discuss the pattern, medications, hydration, and whether you need testing for POTS or another cause.
03 · POTS
What POTS means in plain language
POTS is a syndrome, not just a fast pulse. The standing pattern is what makes it different from many other causes of dizziness.
POTS stands for postural orthostatic tachycardia syndrome. That name describes what happens: symptoms begin or get worse with standing, and the heart rate rises too much for the situation. Postural means related to body position. Orthostatic means upright or standing.
The condition sits under the broader category of autonomic nervous system disorders. That system helps control automatic body functions, including heart rate and blood vessel tone. When it does not respond normally, blood pressure and circulation can be hard to regulate, especially after standing up.
Not everyone with POTS feels the same way. One person may mostly notice dizziness. Another may have racing heart, shakiness, brain fog, nausea, or exercise intolerance. The exact mix matters because it can help a clinician decide whether POTS is the best fit or whether something else explains the symptoms better.
- Symptoms often improve when lying down.
- A single pulse check does not prove POTS.
- The same condition can look different from person to person.
04 · POTS
Symptoms that fit POTS, and symptoms that point elsewhere
Dizziness and palpitations can happen in POTS, but they can also come from several other conditions that need to be ruled out.
Common symptoms include lightheadedness, a pounding or racing heartbeat, shakiness, weakness, fatigue, nausea, blurred vision, headache, sweating, or trouble concentrating after standing up. Some people faint, but fainting is not required for POTS and does not automatically mean POTS is the cause.
The pattern is important. Symptoms that show up after standing still for a long time, in heat, after poor sleep, or after dehydration can fit POTS. Symptoms that come with chest pain, shortness of breath, or an irregular pulse raise a different concern and need more careful review.
Arrhythmias can feel similar because they can cause palpitations, dizziness, fainting, chest discomfort, and shortness of breath. That is one reason clinicians do not assume every fast heartbeat is POTS.
- Keep track of what you were doing right before symptoms started.
- Note whether the heartbeat feels fast, irregular, or both.
- Write down whether lying down makes the symptoms settle.
05 · POTS
Why symptoms flare and what can make them worse
POTS symptoms often flare when circulation is stressed, but a trigger does not tell you the full cause by itself.
Some people notice symptoms after an illness or during a period of less activity. Others notice a slower buildup over time. The supplied evidence supports that autonomic disorders can occur alone or as the result of another disease, and some get better when an underlying disease is treated.
Heat, dehydration, long periods of still standing, poor sleep, alcohol, and sudden exertion can all make upright symptoms feel worse. Large meals can also be rough for some people. These triggers do not prove POTS, but they can explain why symptoms vary from day to day.
Because the same symptoms can come from dehydration, anemia, thyroid disease, medication effects, or a heart rhythm problem, a trigger diary is useful mainly as a clue. It helps a clinician see the pattern and decide what to test.
- Recent illness can matter, but it does not explain everything on its own.
- Heat and dehydration are common symptom amplifiers.
- A symptom diary can make the office visit more useful.
06 · POTS
What clinicians check before calling it POTS
The visit usually focuses on heart rate, blood pressure, and signs of other causes, not on symptoms alone.
A clinician may ask exactly when the symptoms start, whether they happen only when upright, and how quickly they settle after lying down. They may ask about fainting, palpitations, exercise tolerance, weight changes, menstrual blood loss, recent infection, pregnancy, and any new medicines or supplements.
They may check your heart rate and blood pressure lying down and after standing. Depending on the story, they may also order an EKG or blood tests. Those tests help look for arrhythmia, anemia, thyroid disease, dehydration, or other problems that can imitate POTS or make it worse.
This step matters because treating the wrong problem can miss something more serious. A standing heart-rate rise can be one piece of the puzzle, but it is not enough by itself to explain every case of dizziness or palpitations.
- Bring a list of medicines and supplements.
- Write down recent illnesses, blood loss, and pregnancy status if relevant.
- Ask what findings would point away from POTS and toward another cause.
07 · POTS
First steps that often help before medicines
Many people start with practical changes that improve circulation and make standing easier.
Treatment often begins with fluid intake, salt only when a clinician says it is safe, compression garments, slow changes in position, and avoiding long stretches of still standing. These steps can reduce symptoms by helping blood return to the heart and by lowering the stress of standing on the body.
Exercise is often part of care too, but it usually works better when it starts gently and builds slowly. Recumbent or seated activity may be easier at first than upright workouts. The goal is to improve conditioning without forcing repeated symptom flares that set you back.
These changes are not a cure, and they are not the same for everyone. Salt and fluid advice needs extra caution if you have kidney disease, heart disease, or blood pressure problems, because the safest plan depends on your medical background.
- Fluids and salt are not one-size-fits-all.
- Compression can help some people if it fits well.
- Gentle, gradual exercise is usually easier than sudden intense workouts.
08 · POTS
When medicines are considered, and when the problem may be something else
Medicines may help, but the right choice depends on the cause of symptoms and on other health conditions.
If lifestyle measures are not enough, clinicians may consider medicines to control heart rate, support blood pressure, or treat related symptoms. The right choice depends on whether the main issue is fast heart rate, low blood pressure, low blood volume, or an overlap with another condition. That is why treatment is individualized rather than one-size-fits-all.
It is also important not to ignore signs that do not fit simple standing-related symptoms. Chest pain, trouble breathing, fainting that does not quickly clear, a very irregular heartbeat, confusion, or one-sided weakness need emergency care. Those can signal a heart or neurologic problem instead of POTS.
A new medicine can also change the picture. If symptoms started after a prescription change, that deserves prompt review because some medicines can affect heart rate, rhythm, or blood pressure.
- Bring an updated medication list to every visit.
- Ask what a medicine is expected to improve and what side effects to watch for.
- Do not assume a new flare is "just POTS" if the symptoms are different or severe.
09 · FAQ
Questions people ask
Is POTS the same as anxiety?
No. POTS can feel like anxiety because the heart races and the body may feel shaky, but the trigger is often standing and the underlying issue is physiologic. Anxiety can also happen at the same time, so both may need attention.
Can dehydration make POTS symptoms worse?
Yes. Not having enough fluid can make standing symptoms more noticeable by reducing blood volume and making circulation harder. The right fluid plan still needs to be individualized if you have kidney, heart, or blood pressure problems.
Do compression stockings really help?
They can help some people by reducing blood pooling in the legs and abdomen. They are not a cure, and fit matters a lot. A clinician can help you decide whether compression is worth trying and what type makes sense for your symptoms.
What kind of exercise is safest with POTS?
Often the safest starting point is gentle, gradual activity that does not trigger a big flare. Many people begin with seated or recumbent exercise and slowly build from there. If exercise brings on chest pain, severe shortness of breath, or fainting, that needs medical review.
Can POTS happen after an illness?
Some people notice a standing-related symptom pattern after being sick. That does not prove the illness caused it, and it still needs evaluation so dehydration, anemia, thyroid disease, or an arrhythmia are not missed.
When should I worry that it is not POTS?
Worry more if the symptoms include chest pain, shortness of breath, a very irregular heartbeat, one-sided weakness, confusion, or fainting that does not quickly improve. Those symptoms can point to a heart or neurologic emergency instead of a standing-related syndrome.
10 · References
References and supporting evidence
These sources support the points identified below. Source checking is not clinical approval.
- S2: Autonomic Nervous System DisordersMedlinePlus / U.S. National Library of Medicine
Explains the basic autonomic nervous system role behind standing-related heart rate and blood vessel changes. Supports cautious wording that POTS-like symptoms may occur by themselves or alongside another condition. Supports the general caution that autonomic disorders can have variable courses, without promising recovery. Supports urgent-care language for severe breathing or heart symptoms.
- S3: ArrhythmiaMedlinePlus / U.S. National Library of Medicine
Supports the explanation that an irregular or abnormal rhythm can mimic POTS symptoms. Supports the symptom overlap and the need to treat chest pain, fainting, and shortness of breath as potentially serious. Supports mention of EKG as one possible test when clinicians check for a rhythm problem. Supports the differential diagnosis point that thyroid disease can be part of the workup when rhythm symptoms are present.
General information, not a diagnosis. This guide is not a substitute for care from a qualified healthcare professional. For an emergency, call 911 in the US or your local emergency number. Illustrations are conceptual and are not diagnostic images.