Postural Tachycardia Syndrome (POTS)

Overview

Postural tachycardia syndrome, usually called POTS, is a disorder of the autonomic nervous system, the part of the nervous system that automatically controls functions such as heart rate and blood pressure. In POTS, standing up triggers an abnormally large and rapid increase in heart rate. Normally the body adjusts smoothly when a person stands, but in POTS this regulation does not work properly, so the heart races to compensate while blood pools in the lower body.

The result is a collection of symptoms that occur on standing and improve on lying down, including dizziness, a pounding or racing heartbeat, fatigue, and sometimes near-fainting. POTS most often affects young women and can range from a mild nuisance to a condition that significantly limits daily activities, school, or work. It is not usually life-threatening, but it can be disabling, and a combination of lifestyle measures and sometimes medication can substantially improve symptoms.

Symptoms

Symptoms tend to appear or worsen when standing and ease when lying down. They include:

• Lightheadedness or dizziness on standing, sometimes with near-fainting.
• A rapid or pounding heartbeat (palpitations).
• Fatigue that can be severe and persistent.
• Brain fog: Trouble concentrating, thinking clearly, or remembering.
• Other symptoms: Headache, shakiness, sweating, nausea, exercise intolerance, and a bluish or blotchy discoloration of the legs when standing.

Symptoms are often worse in the morning, in hot weather, after meals, during illness, and around menstrual periods. Many people find their symptoms vary from day to day.

Causes

POTS is not a single disease but a syndrome with several possible underlying mechanisms, and in many people the exact cause is not fully understood. Contributing factors and patterns include:

• Following an illness or event: Symptoms often begin after a viral infection, surgery, pregnancy, or a period of prolonged bed rest.
• Abnormal blood vessel control: Blood vessels may not tighten properly on standing, so blood pools in the legs and the heart speeds up to compensate.
• Low blood volume or problems with how the body handles salt and fluid.
• Nerve-related forms in which the nerves controlling blood vessels in the limbs do not work normally.

POTS is also associated with certain conditions, such as joint hypermobility and some autoimmune disorders, in a portion of patients.

Risk Factors

• Being a young woman, roughly between adolescence and age 50
• A recent viral illness, surgery, pregnancy, or major physical stress
• Prolonged bed rest or deconditioning
• Conditions linked to POTS, such as joint hypermobility syndromes
• A family history of similar symptoms in some cases

Diagnosis

POTS is diagnosed by documenting the characteristic rise in heart rate on standing and ruling out other causes:

• Heart rate and blood pressure measurements while lying down and after standing, looking for a sustained large rise in heart rate without a major drop in blood pressure.
• Tilt-table test: Monitoring heart rate and blood pressure while the person is tilted upright on a special table.
• Electrocardiogram (ECG) and heart monitoring to check the heart rhythm.
• Blood tests to look for conditions such as anemia or thyroid problems that can mimic POTS.

Because symptoms overlap with many other conditions, diagnosis can take time and may involve a specialist.

Treatment

Treatment is individualized and usually starts with non-drug measures, adding medication if needed:

• Increasing fluids and salt: Drinking more water and, when advised, raising salt intake to expand blood volume.
• Compression garments: Compression stockings or abdominal binders to reduce blood pooling in the legs.
• Gradual exercise: A structured, progressive program, often starting with reclined or seated exercise, to rebuild fitness; this is one of the most effective treatments.
• Lifestyle adjustments: Avoiding prolonged standing, rising slowly, raising the head of the bed, and managing heat and large meals.
• Medications: Several medicines can help control heart rate or support blood pressure when lifestyle measures are not enough.

Many people improve significantly over time, especially with consistent exercise and fluid management, though management is often ongoing.

Prevention

POTS itself cannot always be prevented, but symptoms can often be reduced and flare-ups limited:

• Stay well hydrated throughout the day
• Stand up slowly and avoid standing still for long periods
• Maintain regular physical activity to prevent deconditioning
• Avoid getting overheated and be cautious in hot weather
• Eat smaller, more frequent meals if large meals worsen symptoms
• Follow your treatment plan consistently, even on good days

When to See a Doctor

See a doctor if you regularly feel dizzy, have a racing heartbeat on standing, or experience persistent fatigue and brain fog that interfere with daily life. Seek prompt or emergency care if you have:

• Fainting, especially with injury
• Chest pain or severe, sustained palpitations
• Shortness of breath that is new or worsening

While POTS is generally not life-threatening, these symptoms should be evaluated to rule out a heart problem.

Related Topics

Frequently Asked Questions

References

1. National Institute of Neurological Disorders and Stroke (NINDS). Postural Tachycardia Syndrome Information.
2. Mayo Clinic. Postural tachycardia syndrome (POTS).
3. MedlinePlus, U.S. National Library of Medicine. Autonomic nervous system disorders.
4. Dysautonomia International. Postural Orthostatic Tachycardia Syndrome.