Learn more about Spoons Of Salt, POTS, and dysautonomia.

What is POTS?
What does POTS stand for?
  • Postural: related to the position of your body
  •  Orthostatic: related to standing upright
  • Tachycardia: increased heart rate
  • Syndrome: a group of symptoms
Why does heart rate increase excessively with POTS?

In most patients with POTS, the structure of the heart itself is normal. POTS symptoms arise from a combination of the following:

  • Lower amount of blood in the circulation.
  • Excessive pooling of blood below the level of the heart when upright.
  • Elevated levels of certain hormones such as epinephrine (also known as adrenaline since it is released by the adrenal glands) and nor-epinephrine (mainly released by nerves).

When we stand, gravity pulls more blood into the lower half of the body. In a healthy person, to ensure that a sufficient amount of blood reaches the brain, the body activates several nervous system responses. One such response is releasing hormones that help tighten blood vessels and cause a modest increase in heart rate. This leads to better blood flow to the heart and brain. Once the brain is receiving enough blood and oxygen, these nervous system responses settle back to normal.

In people with POTS, for unclear reasons that may differ from person to person, the blood vessels don’t respond efficiently to the signal to tighten. As a result, the longer you are upright, the more blood pools in the lower half of your body. This leads to not enough blood returning to the brain, which can be felt as lightheadedness (faintness), brain fog and fatigue. As the nervous system continues to release epinephrine and nor-epinephrine to tighten the blood vessels, the heart rate increases further. This may cause shakiness, forceful or skipped heartbeats, and chest pain.

Some people with POTS can develop hypo-tension (a drop in blood pressure) with prolonged standing (more than three minutes upright). Others can develop an increase in blood pressure (hypertension) when they stand.

Types and Causes of POTS

The causes of POTS vary from person to person. Researchers don’t entirely understand the origins of this disorder. The classification of POTS is the subject of discussion, but most authorities recognize different characteristics in POTS, which occur in some patients more than others. Importantly, these characteristics are not mutually exclusive; person with POTS may experience more than of these at the same time:

Neuropathic POTS is a term used to describe POTS associated with damage to the small fiber nerves (small-fiber neuropathy). These nerves regulate the constriction of the blood vessels in the limbs and abdomen.

Hyperadrenergic POTS is a term used to describe POTS associated with elevated levels of the stress hormone norepinephrine.

Hypovolemic POTS is a term used to describe POTS associated with abnormally low levels of blood (hypovolemia).

Secondary POTS means that POTS is associated with another condition known to potentially cause autonomic neuropathy, such as diabetes, Lyme disease, or autoimmune disorders such as lupus or Sjögren’s syndrome.

What are the symptoms of Postural Orthostatic Tachycardia Syndrome?

POTS symptoms vary from person to person and may include:

  • Severe and/or long-lasting fatigue
  • Lightheadedness with prolonged sitting or standing that can lead to fainting
  • Brain fog: trouble focusing, remembering or paying attention
  • Forceful heartbeats or heart palpitations (a feeling of the heart pounding or skipping a beat)
  • Nausea and vomiting
  • Headaches
  • Excessive sweating
  • Shakiness
  • Intolerance of exercise or a prolonged worsening of general symptoms after increased activity
  • A pale face and purple discoloration of the hands and feet if the limbs are lower than the level of the heart

POTS symptoms typically get worse:

  • In warm environments, such as a hot bath or shower, a hot room or on a hot day
  • In situations involving a lot of standing, such as waiting for a bus or when shopping
  • If fluid and salt intake have not been adequate, such as after skipping a meal

POTS symptoms may also get worse when you get a common cold or an infection. In severe cases, POTS symptoms can prevent a person from being upright for more than a couple of minutes. This can greatly affect all aspects of personal, school, work and social life.

Although the origin of POTS symptoms is physical, sometimes people attribute the symptoms incorrectly to psychological disorders such as anxiety. While some people with POTS have anxiety disorders similar to the general population, POTS is not caused by anxiety.

Can Postural Orthostatic Tachycardia Syndrome be fatal?
How is POTS diagnosed?
Tilt Table Test for POTS

During the tilt table test, you are secured on a table while lying flat. Then the table is raised to an almost upright position. Your heart rate, blood pressure and often blood oxygen and exhaled carbon dioxide levels are measured during this test.

You might have POTS if you meet all three of these criteria:

  • Your body produces an abnormal heart rate response to being upright
  • Your symptoms worsen when upright
  • You don’t develop orthostatic hypo-tension in the first three minutes of testing
Other POTS Tests

In some cases, other tests are warranted. They may include:

  • Valsalva maneuver to test the response of the autonomic nerves that control the heart.

  • Quantitative sudomotor axon reflex test (QSART) to measure response of the autonomic nerves responsible for regulating sweating.

  • Although less common, your physician may also schedule an MRI and other imaging tests to rule out tumors or other abnormalities.
How is POTS treated?
Postural Orthostatic Tachycardia Syndrome Diet
Does Postural Orthostatic Tachycardia Syndrome go away?
Who treats Postural Orthostatic Tachycardia Syndrome?