Heart Races When I Stand Up: Could It Be POTS?

You stand up from the couch and your heart takes off — pounding, racing, maybe with dizziness, shakiness, brain fog, nausea, or a "graying out" of your vision. If this pattern happens repeatedly when you go from sitting or lying to standing, one possible explanation is POTS, or postural orthostatic tachycardia syndrome.

POTS is not simply "heart rate goes up when I stand." The research definition is more specific: an exaggerated, sustained heart-rate rise with upright posture, symptoms that are worse upright and improve when lying down, no orthostatic blood-pressure drop, and no better explanation such as dehydration, anemia, thyroid disease, infection, medication effect, or prolonged bed rest (Heart Rhythm Society consensus statement, 2015; CMAJ, 2022).

What Happens When You Stand (Normally)

Standing up is a small battle with gravity. When you rise, blood naturally pools in your legs and abdomen. Normally, blood vessels constrict and heart rate rises modestly to keep blood flowing to the brain.

In POTS, that upright response is exaggerated. Reviews describe several overlapping mechanisms, including reduced circulating blood volume, impaired venous return, abnormal blood-vessel constriction, and an exaggerated sinus-node response to standing; different mechanisms can overlap in the same person (CMAJ, 2022).

What POTS Is

POTS is a disorder of orthostatic intolerance: symptoms are brought on by upright posture and improve when the person lies down. It involves the autonomic nervous system — the automatic controls for heart rate, blood vessels, and blood pressure — but the syndrome is defined by a clinical pattern, not by one lab test.

The commonly used adult criteria include all of the following:

A sustained heart-rate increase of 30+ beats per minute within 10 minutes of standing or head-up tilt in adults, or 40+ bpm in adolescents.
No orthostatic hypotension, meaning no sustained blood-pressure drop of 20 mm Hg systolic or 10 mm Hg diastolic on standing.
Frequent orthostatic symptoms such as lightheadedness, palpitations, tremor, weakness, blurred vision, fatigue, or exercise intolerance that are worse upright and improve when lying down.
Symptoms present for at least 3 months in many contemporary criteria.
No other condition that better explains the tachycardia, such as dehydration, anemia, fever, pain, infection, hyperthyroidism, medication effects, panic physiology, or prolonged bed rest.

The 2015 Heart Rhythm Society statement describes the same core triad: standing-related symptoms, a 30 bpm adult heart-rate rise (40 bpm in ages 12 to 19), and absence of orthostatic hypotension (Heart Rhythm Society consensus statement, 2015).

Common POTS Symptoms

Racing heart or palpitations on standing
Lightheadedness or dizziness, sometimes near-fainting
Fatigue or exercise intolerance
Brain fog and difficulty concentrating
Shakiness, tremor, sweating, blurred vision, or nausea
Symptoms that improve when you lie back down

POTS often affects adolescent girls and younger adult women, but it can occur outside that group. Symptoms can follow a viral illness, pregnancy, surgery, concussion, or a period of reduced activity; post-viral and post-COVID orthostatic intolerance have also brought more attention to the condition.

POTS vs. a Normal Stand-Up Bump

Almost everyone's heart rate rises a bit on standing — that's normal. POTS is different because the rise is large, sustained, symptomatic, and recurrent, and blood pressure does not show the orthostatic hypotension pattern. A brief head-rush after jumping up quickly can reflect transient blood-pressure dipping, dehydration, heat, missed meals, or medications rather than POTS.

How POTS Is Evaluated

Diagnosis hinges on documenting heart rate and blood pressure during posture change and checking whether the whole clinical picture fits. Orthostatic vital signs are the starting point: the patient rests supine, then pulse and blood pressure are measured after standing, commonly at 1 and 3 minutes in syncope evaluation; POTS-specific protocols often extend measurement out to 10 minutes to capture the sustained heart-rate rise (American Family Physician, 2023; CMAJ, 2022).

Tilt-table testing is not required for every patient, but it can help when the diagnosis is uncertain or when delayed orthostatic hypotension, reflex syncope, POTS, or psychogenic pseudosyncope are being sorted out (American Family Physician, 2023).

A Zio® patch does not diagnose POTS by itself because it does not measure blood pressure or prove orthostatic criteria. What it can do is record heart rhythm and heart-rate trends during daily life. When someone logs "I stood up and my heart raced," the recording can show whether the rhythm was sinus tachycardia — the expected rhythm pattern in POTS — or a different arrhythmia such as SVT or atrial fibrillation that would change the differential.

In a telehealth workflow, rhythm monitoring is most relevant when the clinical question includes "is this sinus tachycardia or a separate arrhythmia?" It is only one piece of the broader orthostatic evaluation.

High Risk Symptoms

POTS itself is generally not framed as immediately life-threatening, but standing-related symptoms paired with the following features are higher risk than routine orthostatic intolerance:

Chest pain or pressure
Fainting (actually losing consciousness), especially with injury
Severe shortness of breath
A racing heart that won't settle even after lying down

Things That Often Help POTS Symptoms

The best-studied first steps are non-drug strategies. Reviews and consensus guidance commonly emphasize:

Fluids and salt to expand circulating volume when appropriate.
Compression garments, especially those that include the abdomen, to reduce blood pooling.
Exercise reconditioning, often starting with recumbent exercise such as rowing, recumbent cycling, or swimming before progressing upright.
Trigger awareness, including heat, dehydration, alcohol, prolonged standing, and rapid posture changes.
Medication review, because stimulants, vasodilators, diuretics, and some other drugs can worsen orthostatic tachycardia.

Medications are individualized when non-drug measures are not enough. Depending on the physiology and symptoms, specialist care may consider options such as beta blockers, ivabradine, midodrine, fludrocortisone, pyridostigmine, or others; none is a one-size-fits-all POTS treatment (CMAJ, 2022).

Sources & Further Reading

This article draws on peer-reviewed clinical literature:

Syncope: Evaluation and Differential Diagnosis. American Family Physician (2023) — orthostatic measurement and tilt-table testing for POTS.
ACC/AHA/HRS Syncope Evaluation and Treatment Guidelines. American Family Physician (2018) — ambulatory monitoring for position-related symptoms.
2015 Heart Rhythm Society Expert Consensus Statement on POTS, IST, and Vasovagal Syncope. Heart Rhythm (2015) — consensus diagnostic criteria for POTS.
Diagnosis and Management of Postural Orthostatic Tachycardia Syndrome. CMAJ (2022) — contemporary diagnostic criteria, exclusions, mechanisms, and management overview.

The Bottom Line

A heart that consistently races with dizziness on standing can raise the question of POTS, but the research criteria require more than a fast pulse: sustained orthostatic tachycardia, no orthostatic hypotension, chronic upright symptoms, and exclusion of other causes. Rhythm monitoring can help document whether the racing is sinus tachycardia or another arrhythmia, but POTS evaluation still depends on posture-linked heart-rate and blood-pressure measurement.

This blog post is for educational purposes only and is not a substitute for professional medical advice. If you're experiencing chest pain, severe shortness of breath, or think you're having a heart attack, call 911 immediately.