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POTS symptoms arise from a combination of the following:. Elevated levels of certain hormones such as epinephrine also known as adrenaline since it is released by the adrenal glands and norepinephrine 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.
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 norepinephrine 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 hypotension 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. The causes of POTS vary from person to person. 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:. These nerves regulate the constriction of the blood vessels in the limbs and abdomen.
A pale face and purple discoloration of the hands and feet if the limbs are lower than the level of the heart. 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 POTS can be life-changing, it is not life-threatening. One of the biggest risks for people with POTS is falls due to fainting. Not everyone who has POTS faints. And, for those who do, it may be a rare event. The majority of them are women, although men may also develop POTS.
POTS is less common in young children, but it affects adolescents, and symptoms often develop during puberty. POTS may begin after an apparent or confirmed viral illness, but it can also appear following surgery and other health events. A mutation in the norepinephrine transporter gene appears to affect only a tiny portion of POTS patients. Among genetic factors, there is a strong association between POTS and various joint hypermobility disorders, including Ehlers-Danlos syndrome.
Recent research has also highlighted an overlap between POTS, joint hypermobility and mast cell disorders, some of which have a genetic origin. Although many people recover quickly from COVID, the disease caused by the coronavirus, others who recover may continue to experience symptoms for months. In some studies, slightly more than half of pregnant women with POTS felt better than usual during their pregnancies, which might be due to the increase in blood volume that is present after the first few weeks of pregnancy.
Other complications of pregnancy appear to occur at about the same rate for women with POTS, and their newborns seem to be as healthy as infants born to mothers without POTS. POTS diagnosis can be complicated because the symptoms can affect a wide range of organ systems, and the most bothersome symptom for each patient may differ. In most instances, symptoms have been present for months before the diagnosis is made.
Doctors start by doing a complete physical exam and taking a medical history. POTS causes a heart rate increase of 40 or more beats per minute within 10 minutes of when someone moves from a supine lying down position to a standing one.
The heart rate goes up dramatically, with little if any drop in blood pressure. Doctors can measure this easily. Sometimes, doctors do a "tilt-table test.
Doctors also make sure the problem isn't due to anything besides the autonomic nervous system. Depending on the symptoms, tests might be done on other parts of the body. These might check the blood, heart, brain, eyes, ears, kidneys, muscles, nerves, hormones, digestive tract, and more. Typically, a diagnosis of POTS is confirmed when symptoms have lasted for several months and no other causes are found.
If someone has POTS, the medical team will look for reasons that the autonomic nervous system doesn't respond normally to standing. Finding an answer can help treatments work well. POTS is a chronic long-term problem. So doctors try to prevent and manage the things that cause it. That way, a child or teen doesn't have to take medicines for a long time. The autonomic nervous system is involved in many body functions, so managing all the symptoms related to it can be hard.
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