POTS and Dizziness Explained: Understanding Postural Orthostatic Tachycardia Syndrome and How It’s Diagnosed

Feeling lightheaded every time you stand up, noticing your heart race for “no reason,” and being told “your tests are normal” can be confusing and frustrating. For some people, these symptoms are part of a condition known as Postural Orthostatic Tachycardia Syndrome (POTS).

This guide explains what POTS is, why it causes dizziness and rapid heart rate, how it is typically diagnosed, and what questions and next steps people often consider. It is designed to inform and clarify, not to diagnose or recommend specific treatments.

What Is POTS?

Postural Orthostatic Tachycardia Syndrome (POTS) is a condition that affects how the body regulates blood flow and heart rate when changing position, especially moving from lying down or sitting to standing.

• “Postural” refers to body position.
• “Orthostatic” relates to standing upright.
• “Tachycardia” means an abnormally fast heart rate.
• “Syndrome” indicates a group of symptoms that tend to occur together.

In simple terms, POTS is a type of dysautonomia—a problem with the autonomic nervous system, which controls automatic body functions such as heart rate, blood pressure, and digestion.

When a person with POTS stands up, their body may struggle to raise blood pressure and move blood efficiently from the lower body back up to the heart and brain. The heart often compensates by beating much faster, which can cause:

• Dizziness or lightheadedness
• A racing heartbeat
• Weakness or fatigue
• Feeling close to fainting

POTS is considered a chronic condition for many people, but the severity and pattern of symptoms can vary widely from person to person.

How the Body Normally Handles Standing Up

To understand POTS, it helps to know what usually happens when a person stands.

Normal Blood Flow on Standing

When a healthy person stands:

1. Gravity pulls blood toward the legs and lower body.
2. Less blood returns to the heart for a few moments.
3. Blood pressure may briefly drop.
4. The autonomic nervous system reacts quickly:
   • Blood vessels in the legs and abdomen tighten (constrict).
   • Heart rate increases slightly.
   • Blood pressure stabilizes so the brain continues receiving enough blood.

Most people feel nothing more than a brief, barely noticeable adjustment.

What Can Happen in POTS

In POTS, some of these automatic responses do not work as smoothly. Patterns often include:

• Excessive heart rate increase on standing
• Difficulty tightening blood vessels in the legs and lower body
• Pooling of blood in the lower body
• A feeling that blood flow to the brain is reduced, leading to dizziness and “brain fog”

The body tries to compensate, often with a sustained rapid heartbeat rather than a brief adjustment.

Common Symptoms of POTS

POTS can affect many systems in the body. Symptoms are often worse when standing, sitting upright, or in warm environments, and may improve when lying down.

Core Orthostatic Symptoms

These signs are closely related to changes in position:

• Dizziness or lightheadedness on standing
• Rapid heart rate (palpitations) when upright
• Near-fainting or fainting (syncope)
• Blurred vision or dimming of vision when standing
• Weakness, shakiness, or feeling “drained” after standing

Some people notice that symptoms worsen:

• In hot showers or baths
• In crowded or warm rooms
• After eating large meals
• During prolonged standing (queues, lines, cooking, showering)

General and “Whole-Body” Symptoms

Because POTS involves the autonomic nervous system, symptoms can extend beyond heart rate and dizziness:

• Fatigue, sometimes severe and long-lasting
• Exercise intolerance, or feeling unusually wiped out after activity
• Brain fog—difficulty concentrating, memory problems, or slow thinking
• Headaches or migraines
• Nausea, abdominal discomfort, or bloating
• Sleep disturbances (trouble falling or staying asleep, unrefreshing sleep)
• Temperature sensitivity (feeling unusually hot or cold)
• Tremors or internal shakiness

Not everyone with POTS experiences all these symptoms. The pattern can be different from person to person and can change over time.

Why POTS Causes Dizziness and a Rapid Heart Rate

The key features of POTS—dizziness and rapid heart rate on standing—come from how the body is trying to cope with gravity and circulation challenges.

Blood Pooling and Reduced Brain Blood Flow

In POTS, when a person stands, more blood than usual may pool in the lower body because:

• Blood vessels do not tighten efficiently.
• The muscles of the legs may not pump blood back toward the heart effectively.

If less blood returns to the heart, then less is pumped out to the body and brain. The brain is very sensitive to changes in blood flow, so even a modest reduction can lead to:

• Lightheadedness
• Blurred vision
• Ringing in the ears
• A sense of “about to black out”

Heart Rate Compensation

To help maintain circulation:

• The heart increases its rate (beats per minute) to keep blood moving.
• In POTS, this increase is often exaggerated and sustained, even though blood pressure may not drop dramatically.

People may feel:

• Pounding or racing heart
• Awareness of heartbeats in the chest, neck, or head
• Occasional chest discomfort or shortness of breath

The fast heart rate is often alarming, but in POTS it is usually a compensatory response, not necessarily a sign of heart muscle damage or blockage.

Possible Triggers and Associated Conditions

POTS does not have a single universal cause. Instead, it appears to arise from a combination of genetic, neurologic, cardiovascular, immune, and environmental factors.

Common patterns reported by people later diagnosed with POTS include:

• A trigger event, such as:
  • A viral or bacterial illness
  • A period of bed rest or deconditioning
  • Surgery or physical trauma
  • A major hormonal shift (for example, around puberty or pregnancy)
• A history of other conditions, such as:
  • Certain autoimmune conditions
  • Joint hypermobility or related connective tissue differences
  • Migraine
  • Chronic pain conditions

Some people with POTS can trace their symptoms back to a clear turning point, while others notice a more gradual onset. Many individuals are diagnosed in adolescence or early adulthood, but POTS can affect people of various ages.

How POTS Is Typically Diagnosed

Diagnosis is usually based on:

1. Symptoms that fit the pattern of POTS.
2. Heart rate and blood pressure changes during posture changes.
3. Ruling out other conditions that could explain the symptoms.

Diagnosis is often made by clinicians familiar with autonomic conditions, such as certain cardiologists, neurologists, or general physicians with an interest in autonomic disorders.

Key Diagnostic Features

POTS is generally defined by:

• A sustained, significant increase in heart rate within several minutes of standing or head-up tilt, without a large drop in blood pressure, accompanied by:
• Frequent symptoms of orthostatic intolerance, such as dizziness, palpitations, and fatigue, that improve when lying down, and
• Symptoms lasting for a considerable period, often several months or more.

Exact criteria can vary depending on age and clinical guidelines, but the overall concept is consistent: unusual heart rate response to standing with chronic symptoms.

Common Tests Used in POTS Evaluation

Different tests may be used depending on the clinician, the setting, and individual circumstances. Not everyone needs every test.

1. Detailed Medical History and Symptom Review

This often includes:

• When symptoms started and how they have changed
• Triggers (heat, meals, stress, menstrual cycle, illness, etc.)
• Fainting or near-fainting episodes
• Exercise tolerance
• Sleep and energy patterns
• Current medications, supplements, and caffeine intake
• Family history of similar symptoms, fainting, heart problems, or autoimmune conditions

This conversation can be one of the most important “tests,” as it guides everything that follows.

2. Physical Examination

A physical exam may focus on:

• Heart and lung sounds
• Blood pressure and heart rate in different positions
• Signs of joint hypermobility
• Skin, circulation, and signs of fluid status (hydration)
• Neurologic exam for strength, reflexes, and coordination

3. Orthostatic Vital Signs (Lying-to-Standing Test)

A simple in-office test may involve:

1. Resting lying down for several minutes.
2. Measuring heart rate and blood pressure while lying.
3. Standing up (or occasionally sitting up first, then standing).
4. Repeating measurements at intervals (for example, 1, 3, 5, and 10 minutes).

In people with POTS:

• Heart rate often jumps significantly when standing and stays elevated.
• Blood pressure may remain relatively stable or fluctuate slightly.

This test is usually quick, low-tech, and a common first step.

4. Tilt Table Test

A tilt table test is a more controlled way to evaluate how the body responds to changes in position. It is typically done in a hospital or specialized clinic.

The general idea:

• The person lies flat on a special table.
• Heart rate and blood pressure are monitored continuously.
• The table is tilted to raise the upper body while the feet remain down, simulating standing without active muscle use.
• Clinicians watch for heart rate changes, blood pressure changes, and symptom reproduction.

Tilt table testing can help:

• Support a POTS diagnosis
• Distinguish POTS from other conditions such as certain forms of fainting or blood pressure problems

5. Blood and Other Laboratory Tests

Laboratory testing is often used to rule out other causes of similar symptoms, such as:

• Anemia
• Thyroid disorders
• Electrolyte imbalances
• Nutritional deficiencies (for example, vitamin B12)
• Hormonal issues
• Inflammatory or autoimmune conditions

These tests do not “prove” POTS but help ensure that POTS is not being confused with another, more easily treatable condition.

6. Heart and Nervous System Testing

Depending on the situation, clinicians may also use:

• Electrocardiogram (ECG/EKG) to look at heart rhythm
• Holter monitor or event monitor to track heart rate and rhythm over days or weeks
• Echocardiogram (heart ultrasound) to check heart structure and function
• Autonomic function tests, such as deep breathing tests or a Valsalva maneuver assessment, to see how the autonomic nervous system reacts

These tests help identify or exclude structural heart disease, dangerous arrhythmias, or other autonomic disorders.

How POTS Differs from Other Causes of Dizziness

Many conditions can cause dizziness, rapid heart rate, or fatigue. Sorting them out is a major part of the diagnostic process.

Here is a simplified comparison:

This table is simplified and not a diagnostic tool, but it illustrates why careful evaluation is needed. Many conditions overlap in symptoms but differ in underlying cause.

Living with POTS: Daily Experiences and Challenges

People with POTS often describe that everyday tasks require extra planning and energy. Common experiences include:

• Needing to sit or lie down frequently
• Taking breaks while showering, cooking, or shopping
• Being unable to stand still for long (queues, public transport, lines)
• Feeling exhausted after relatively mild physical or mental effort
• Having “good days” and “bad days” without a clear pattern

Symptoms may also fluctuate with:

• Hydration status
• Sleep quality
• Hormonal cycles
• Illness or infection
• Stress, both physical and emotional

Over time, some individuals learn to recognize early warning signs and adjust activity, posture, or environment to reduce symptom flare-ups.

Practical Tips People Commonly Explore with Clinicians

People frequently discuss self-management strategies with clinicians to help reduce symptom impact. These approaches are personalized and not suitable or effective for everyone, but they commonly appear in POTS-focused care.

Here is a simple, non-prescriptive overview of strategies that individuals may explore in partnership with a healthcare professional:

Everyday Strategies People Often Consider

• Position changes gradually

  • Avoid standing up too quickly from lying or sitting.
  • Pause at the edge of the bed before fully standing.

• Hydration and salt intake (under medical guidance)

  • Many people with POTS are advised to discuss with clinicians whether increasing fluids and adjusting dietary salt might be useful.
  • This is highly individualized and not appropriate for everyone, especially those with certain kidney or heart conditions.

• Compression garments

  • Some individuals find that waist-high or thigh-high compression stockings or abdominal binders help reduce blood pooling in the legs and abdomen.

• Activity pacing

  • Breaking tasks into smaller chunks with rest breaks.
  • Alternating physical and mental tasks to avoid overexertion.

• Seated or reclining options

  • Sitting while doing activities like styling hair, cooking prep, or brushing teeth.
  • Using shower chairs or stools.

• Environmental awareness

  • Avoiding overly hot environments when possible.
  • Recognizing that hot showers, saunas, or hot tubs may worsen symptoms for some people.

Because POTS often co-exists with other conditions, strategies can vary significantly. A plan that works well for one individual may not be suitable for another.

Key Takeaways at a Glance 🌟

Here is a quick summary of the most important ideas:

• 🧠 POTS affects the autonomic nervous system, disrupting normal control of heart rate and blood flow when standing.
• 💓 Rapid heart rate on standing is a defining feature, often without a major drop in blood pressure.
• 😵 Dizziness, lightheadedness, and fatigue are common and can significantly affect daily life.
• 🔍 Diagnosis relies on symptoms, lying-to-standing heart rate and blood pressure changes, and exclusion of other causes.
• 🧪 Tests may include orthostatic vitals, tilt table tests, heart monitors, blood work, and autonomic function tests.
• 🔄 Symptoms often fluctuate, influenced by posture, temperature, hydration, illness, and stress.
• 🧭 Self-management is individualized, and people often work closely with healthcare professionals to explore options.

Questions People Commonly Ask About POTS

Understanding POTS often leads to new questions. Here are some that frequently come up, along with general informational answers.

Is POTS Dangerous?

POTS can be highly disruptive and distressing, but it is generally considered a functional circulation problem, not a direct sign of heart muscle damage or clogged arteries.

• Fainting or near-fainting can lead to injuries from falls.
• Rapid heart rate and dizziness can cause anxiety and fear.
• Quality of life can be significantly affected.

However, in many cases, POTS does not progress to life-threatening heart disease. Ongoing care helps ensure that no other serious conditions are missed and that symptoms are monitored over time.

Can POTS Go Away?

Experiences vary:

• Some people see significant improvement over time, especially with supportive management and gradual conditioning.
• Others have long-term, fluctuating symptoms that require ongoing strategies and adjustments.
• For some, POTS appears to be part of a broader health picture, such as an underlying autoimmune or connective tissue condition, and may persist alongside it.

Because of this variability, long-term outlooks are usually discussed on a case-by-case basis.

Is POTS “Just Anxiety”?

POTS and anxiety can overlap in symptoms—both can involve:

• Rapid heartbeat
• Shortness of breath
• Sweating
• Feeling faint or shaky

But POTS is fundamentally related to autonomic and circulatory responses to posture, while anxiety is primarily a mental health condition involving emotional and cognitive patterns.

Some people with POTS develop anxiety after experiencing frightening physical symptoms and repeated “normal test” results. Others may have both conditions independently. Evaluation typically looks at both physical and mental health to understand the full picture.

Preparing to Talk With a Healthcare Professional

For people who suspect they might have POTS or a related condition, preparing for a visit can help make the conversation more productive.

Helpful Information to Track 📒

People often find it useful to bring:

• A brief symptom diary:
  • When symptoms occur
  • What seems to trigger or worsen them
  • What position they are in (lying, sitting, standing)
• A list of current medications, supplements, and caffeine use
• Notes about fainting episodes, if any:
  • What happened just before
  • How long they were out (if known)
  • How they felt afterward
• A family history of:
  • Fainting
  • Heart rhythm problems
  • Autonomic symptoms
  • Autoimmune conditions

Questions People Often Ask Their Clinician

• What conditions might be causing my symptoms?
• Could my symptoms be related to posture or heart rate changes?
• Which tests, if any, are appropriate to explore this further?
• Are there daily strategies I could try under your guidance?
• Is there someone with experience in autonomic disorders you would recommend I see?

These questions do not demand a specific diagnosis; they simply help open a collaborative, informed discussion.

How POTS Fits into the Bigger Picture of Health

POTS is increasingly recognized as part of a broader category of autonomic nervous system disorders and circulatory regulation problems. For some people, it appears alongside:

• Migraine
• Joint hypermobility
• Autoimmune conditions
• Chronic pain or fatigue syndromes

Because of this, evaluation and care often involve more than one specialty. A person might see:

• A cardiologist (especially those focusing on arrhythmias or syncope)
• A neurologist (particularly those with autonomic expertise)
• A general physician or internist who coordinates care
• Other professionals, such as physical therapists, psychologists, or occupational therapists, depending on symptoms

The aim is typically to build a multidimensional understanding of the person’s health, rather than viewing POTS in isolation.

Bringing It All Together

POTS is more than just “getting dizzy when you stand up.” It reflects a complex interaction between the heart, blood vessels, nervous system, and environment.

Key points to remember:

• The hallmark of POTS is a significant, sustained increase in heart rate when standing, usually without a major blood pressure drop, combined with chronic symptoms like dizziness, palpitations, and fatigue.
• Diagnosis often involves careful history-taking, lying-to-standing measurements, and tests that look at heart rhythm, blood pressure control, and overall health.
• POTS can have a major impact on daily life, but understanding what is happening can provide clarity, reduce fear, and support more focused conversations with healthcare professionals.
• Management is highly individualized and often includes lifestyle adaptations, supportive measures, and, when appropriate, medical therapies chosen and supervised by clinicians.

For anyone living with unexplained dizziness, rapid heart rate, and exhaustion—especially linked to standing—learning about POTS can be an important step toward better understanding their symptoms and exploring informed, collaborative care.