Postural orthostatic tachycardia syndrome due to NET deficiency is a rare form of POTS that affects how the body handles norepinephrine, a chemical that helps control heart rate and blood pressure. People with this condition often feel lightheaded, shaky, weak, or faint when they stand up, and some notice palpitations, tiredness, or trouble thinking clearly. The condition often begins in the teen years or early adulthood and may be long lasting, although day-to-day severity can vary. Not everyone will have the same experience. Postural orthostatic tachycardia syndrome due to NET deficiency is not usually thought to shorten life, and treatment focuses on managing early symptoms of POTS with fluids, extra salt when appropriate, exercise plans, compression garments, and sometimes medication.
How many people live with Postural orthostatic tachycardia syndrome due to net deficiency?
No reliable population count is available for the very rare inherited form of postural orthostatic tachycardia syndrome caused by NET deficiency, either worldwide or in the United States. For POTS overall, about 8 to 80 million people worldwide may be living with it, depending on how it is defined and diagnosed (Arnold et al., 2022), and about 1 to 3 million people in the United States are estimated to have it (National Institute of Neurological Disorders and Stroke, 2024), but the NET-deficiency form has been reported too rarely for its own global or U.S. estimate.
Overview
Postural orthostatic tachycardia syndrome due to net deficiencySymptoms
Postural orthostatic tachycardia syndrome due to NET deficiency often causes a fast heartbeat when standing, along with dizziness, fainting, shakiness, fatigue, and trouble concentrating. Some also notice nausea, headaches, or feeling worse after exercise or long periods upright.
Outlook and prognosis
With postural orthostatic tachycardia syndrome due to NET deficiency, day-to-day symptoms often continue over time, but many improve with careful treatment, hydration, salt, and activity pacing. Outlook varies, and follow-up matters because fainting, fatigue, and exercise tolerance can change.
Causes and risk factors
Postural orthostatic tachycardia syndrome due to NET deficiency is usually linked to a change in the SLC6A2 gene, sometimes inherited and sometimes new. Family history can raise risk. Dehydration, heat, illness, and long bed rest can worsen symptoms.
Genetic influences
Genetics are central in postural orthostatic tachycardia syndrome due to NET deficiency, because changes in the SLC6A2 gene can directly reduce norepinephrine transporter function. In some families, this inherited change helps explain early symptoms of postural orthostatic tachycardia syndrome.
Diagnosis
Diagnosis of postural orthostatic tachycardia syndrome due to NET deficiency starts with symptoms, heart rate and blood pressure changes on standing, and a standing or tilt-table test. Doctors may confirm it with genetic tests when NET deficiency is suspected.
Treatment and drugs
Treatment for postural orthostatic tachycardia syndrome due to NET deficiency often combines extra fluids and salt, compression garments, and graded exercise. Some may also need medicines to steady heart rate or reduce standing symptoms, with care tailored to daily triggers and response.
Symptoms
With postural orthostatic tachycardia syndrome due to NET deficiency, many of the main signs show up when someone moves from lying or sitting to standing. The body has trouble handling norepinephrine normally, so standing can trigger a fast pulse, lightheadedness, shakiness, and marked fatigue. The early features of postural orthostatic tachycardia syndrome due to NET deficiency are often easy to mistake for dehydration, anxiety, or simply overdoing it. Signs vary from person to person and can change over time.
Standing up can make the heart race much more than expected, even after only a few minutes. Many living with postural orthostatic tachycardia syndrome due to NET deficiency notice pounding in the chest or a strong awareness of each heartbeat.
Blood flow control can be off when upright, causing dizziness, blurred vision, feeling faint, or actually fainting. This may show up after getting out of bed, standing in line, or taking a hot shower.
Tiredness can be out of proportion to activity, and rest does not always fully reset energy. What once felt effortless can start to require more energy or focus.
Many people have trouble concentrating, finding words, or keeping track of steps in a task when symptoms flare. Day to day, it can feel like your mind slows down when your body has been upright too long.
How people usually first notice Postural orthostatic tachycardia syndrome due to net deficiency?
Many people first notice postural orthostatic tachycardia syndrome due to NET deficiency when standing up starts to feel unusually hard: their heart races, they feel lightheaded, shaky, weak, or close to fainting, even though they were fine sitting or lying down. The first signs of postural orthostatic tachycardia syndrome due to NET deficiency often show up in the teens or early adult years and may be most obvious after getting out of bed, standing in line, exercising, being in heat, or after dehydration. Because these symptoms can look like anxiety, simple fainting, or just “poor fitness,” families and doctors often first notice a pattern of repeated fast heartbeat and dizziness triggered by being upright.
Types of Postural orthostatic tachycardia syndrome due to net deficiency
No distinct types of Postural orthostatic tachycardia syndrome due to NET deficiency are widely recognized.
Can I slow down the onset of symptoms?
Probably not in a proven way: for this rare form of postural orthostatic tachycardia syndrome, caused by a built-in problem in how the body handles a chemical that helps control heart rate and blood pressure, there is no strong evidence that lifestyle changes or medicines can meaningfully delay when symptoms first begin. What does seem to help is symptom control after they start; staying well hydrated, using enough salt if your clinician recommends it, building up physical conditioning gradually, getting enough sleep, and avoiding triggers like heat or long periods of standing may reduce flares, but that is not the same as preventing the condition. There are no well-established screening tests or preventive medicines to stop it from starting, but early care can still help many people with this condition feel better and stay more active.
What genetics can tell you about symptoms
In this rare form of postural orthostatic tachycardia syndrome, genetics can be very informative because changes affecting the norepinephrine transporter, a protein that helps clear stress signals from nerves, can directly lead to the fast heartbeat and standing intolerance that define the condition. These genetic changes may help explain why some people have more severe symptoms, such as marked racing of the heart, dizziness, shakiness, anxiety-like feelings, or trouble with exercise, but they do not always predict exactly which symptoms will happen in any one person. Genetics can point to the underlying cause, yet age of onset and day-to-day symptom burden can still vary from one person to another.
Causes and risk factors
The main cause of postural orthostatic tachycardia syndrome due to NET deficiency is a change in the SLC6A2 gene, and it may be inherited or new in a family. This change weakens the norepinephrine transporter, so the body has more trouble clearing norepinephrine after you stand. Having a gene change doesn’t mean you’ll definitely develop the condition. Biologic factors such as puberty, hormonal shifts, pregnancy, or illness can make symptoms more likely or more noticeable. Heat, dehydration, poor sleep, alcohol, and long periods of bed rest can also trigger or worsen this form of POTS.
What are the most common causes or risk factors?
The main cause of this form of POTS is a problem with the body’s norepinephrine transporter, which normally helps clear away an adrenaline-like stress signal after you stand up; in some people, this is due to an inherited gene change. It can also happen when this transporter does not work well even without a known family history, and symptoms may start or get worse after a viral illness, surgery, pregnancy, injury, or long periods of bed rest. POTS is also seen more often in teens, young adults, and females, which can raise the chance of developing symptoms.
Environmental and biological risk factors
When doctors look at risk factors for postural orthostatic tachycardia syndrome due to NET deficiency, the strongest evidence points to a problem in how the body clears norepinephrine, a stress-related chemical. Some risks are carried inside the body, others come from the world around us. For this rare form, body-based causes are much better established than outside exposures.
The clearest biological risk factor is reduced norepinephrine transporter activity, which means norepinephrine is not cleared as efficiently as it should be. That can make this form of POTS more likely by driving an exaggerated heart-rate response on standing.
In some people, the transporter works poorly because of changes in how it is built or regulated within the body. This is a built-in biological vulnerability, not something caused by everyday habits.
Some medicines that block norepinephrine reuptake can trigger a similar pattern or uncover an underlying vulnerability. This can happen with certain antidepressants and some medicines used for attention problems, so a medication review is often important.
Genetic risk factors
When people ask about the genetic causes of postural orthostatic tachycardia syndrome due to NET deficiency, the answer mainly points to one gene. This rare form of POTS is linked to changes in SLC6A2, which makes the norepinephrine transporter, also called NET. When NET does not work properly, nerve signals that help steady heart rate and blood pressure after standing can be harder for the body to control.
SLC6A2 changes: The main known genetic cause is a harmful change in SLC6A2, the gene that makes the norepinephrine transporter. If this transporter is weak or missing, norepinephrine is not cleared normally, which can make heart rate control on standing less stable.
Inherited pattern: In the few families described so far, this condition appears to follow an autosomal dominant pattern. That means one altered copy of SLC6A2 may be enough to raise risk, and an affected parent can pass that risk to a child.
Family history: A close relative with postural orthostatic tachycardia syndrome due to NET deficiency can increase the chance that the same gene change runs in the family. A family history of early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency can be an important clue, although genetic testing is usually needed to confirm it.
Lifestyle risk factors
Lifestyle habits do not cause postural orthostatic tachycardia syndrome due to NET deficiency, but they can strongly influence day-to-day symptoms and flare frequency. When people ask how lifestyle affects postural orthostatic tachycardia syndrome due to NET deficiency, the main issues are blood volume, venous pooling, heat stress, physical deconditioning, and triggers that amplify tachycardia. Practical adjustments can reduce dizziness, palpitations, fatigue, and exercise intolerance.
Low fluid intake can worsen low circulating volume and make standing symptoms more intense. Steady hydration may help reduce dizziness, rapid heart rate, and presyncope in people with this form of POTS.
Too little dietary salt can make it harder to maintain blood volume and may aggravate orthostatic intolerance. If a clinician has advised higher sodium intake, following that plan can improve standing tolerance and lessen symptom flares.
Large meals, high-carbohydrate meals, and alcohol can shift blood toward the gut and worsen post-meal tachycardia or lightheadedness. Smaller, more frequent meals may help limit these symptom swings.
Physical deconditioning can intensify exercise intolerance and make orthostatic symptoms worse over time. Graded, mostly recumbent or seated exercise may improve conditioning and help the body handle upright posture more effectively.
Risk prevention
For people living with postural orthostatic tachycardia syndrome due to NET deficiency, there is usually no proven way to prevent the condition itself because it relates to an inherited problem in how the body handles norepinephrine. Prevention is mostly about lowering the chance of symptom flare-ups, reducing falls or fainting, and protecting day-to-day function. Many with postural orthostatic tachycardia syndrome due to NET deficiency find that symptoms are easier to manage when triggers are recognized early and daily habits stay consistent. Prevention is flexible—it adapts to your life and health background.
Drinking enough fluids each day can help maintain blood volume and may reduce dizziness when standing. Many people with postural orthostatic tachycardia syndrome due to NET deficiency do better when they drink regularly through the day instead of waiting until they feel thirsty.
If your clinician says it is safe, extra salt may help your body hold on to fluid and support blood pressure when upright. This can be an important prevention step for symptom flares in postural orthostatic tachycardia syndrome due to NET deficiency, but it is not right for everyone.
Standing up gradually can lower the chance of a sudden racing heart, lightheadedness, or fainting. For many, this means sitting at the edge of the bed for a minute before getting up, especially during early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency.
Hot showers, hot rooms, and long time in the sun can widen blood vessels and make symptoms worse. Keeping cool with lighter clothing, shade, or air conditioning may help prevent episodes.
Can you prevent Postural orthostatic tachycardia syndrome due to net deficiency?
No, this rare inherited form of postural orthostatic tachycardia syndrome usually cannot be prevented because it is caused by a change in how the body handles certain nerve signals. Some may be able to lower the chance of symptoms being triggered or made worse by avoiding dehydration, overheating, and long periods of standing, but that does not prevent the condition itself.
Transmission
Postural orthostatic tachycardia syndrome due to NET deficiency is not infectious, so you cannot catch it from another person through the air, touch, food, or body fluids. For many living with this condition, the question is not about spread but about how postural orthostatic tachycardia syndrome due to NET deficiency is inherited.
This rare form is linked to a change in a gene that affects the norepinephrine transporter, and that change may be passed from a parent to a child; in some families, it may also appear for the first time in one person. Because this condition is uncommon and inheritance can vary by the exact gene change, a genetics specialist can help explain the chance of it being passed on and what it may mean for relatives.
When to test your genes
Consider genetic testing if POTS begins early, runs in your family, or comes with unusually strong reactions to standing, exercise, or medicines that affect norepinephrine. In rare families with norepinephrine transporter deficiency, finding the variant can confirm the cause and help clinicians choose treatments more carefully.
Diagnosis
People with postural orthostatic tachycardia syndrome due to NET deficiency often seek help after repeated episodes of feeling faint, shaky, or unusually fast-hearted when they stand up. Doctors usually begin by looking at the pattern of symptoms, especially whether they improve when lying down and return with standing. The diagnosis of postural orthostatic tachycardia syndrome due to NET deficiency is usually based on these clinical features and then confirmed with tests that show an abnormal heart rate response and, in some cases, a gene change linked to the condition.
A clinician asks about dizziness, palpitations, fatigue, brain fog, and near-fainting that happen after standing. A detailed family and health history can help show whether symptoms fit a form of POTS and whether a hereditary cause is possible.
Heart rate and blood pressure are checked while lying down and again after standing for several minutes. In many people with POTS, the heart rate rises more than expected without a major drop in blood pressure.
If the bedside standing test is unclear, your provider may suggest a tilt table test to look closer. This test measures how the body responds when the table moves from flat to upright and can support how POTS is diagnosed.
Blood tests and other lab tests may help rule out common conditions such as dehydration, anemia, thyroid disease, or low blood volume. This matters because several problems can mimic POTS symptoms.
How is Postural orthostatic tachycardia syndrome due to net deficiency diagnosed?
This rare form of POTS is usually diagnosed by hearing about the pattern of symptoms and checking heart rate and blood pressure while a person is lying down and then standing, or during a tilt-table test, which safely mimics standing. Doctors look for a much bigger-than-normal jump in heart rate within 10 minutes of standing, usually without a large drop in blood pressure, and they also do tests to rule out other causes of dizziness or a racing heart. If doctors think the problem may be caused by a rare inherited change affecting how nerve signals handle stress chemicals in the body, genetic testing can help confirm it.
Stages of Postural orthostatic tachycardia syndrome due to net deficiency
Postural orthostatic tachycardia syndrome due to NET deficiency does not have defined progression stages. This is because it is usually identified by a pattern of symptoms that happen when standing up, rather than a steady step-by-step decline over time. Doctors usually start with a conversation about symptoms such as a racing heartbeat, dizziness, fatigue, and trouble concentrating, including early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency, and then check heart rate and blood pressure lying down and standing. Monitoring often focuses on how symptoms affect daily life over time and may include a standing test or tilt table test to confirm the pattern.
Outlook and prognosis
The outlook for postural orthostatic tachycardia syndrome due to NET deficiency is variable, but many affected people have chronic symptoms that can fluctuate over time rather than a steadily worsening disease course. With individualized treatment, including measures to improve blood volume, reduce orthostatic stress, and manage heart rate and triggers, many patients can achieve meaningful symptom control and better daily functioning, although full remission is not guaranteed. Quality of life may be substantially affected by dizziness, palpitations, fatigue, exercise intolerance, and difficulty standing for long periods, and some people remain significantly limited despite therapy. Current evidence does not suggest that this condition usually shortens life expectancy on its own, and mortality appears to be low, but severe symptoms can increase the risk of falls, injury, and complications related to deconditioning. Because NET deficiency is rare, long-term prognosis data are limited, so follow-up with clinicians familiar with autonomic disorders is important. Genetic counseling may also be helpful for affected families when a hereditary cause is confirmed or strongly suspected.
Long-term effects
For many, postural orthostatic tachycardia syndrome due to NET deficiency affects everyday life most when standing, walking, showering, or trying to stay active for long periods. The long-term picture is often uneven: some people have persistent problems over years, while others improve somewhat with age or treatment. Because NET deficiency is very rare, long-term effects vary widely, but doctors most often watch for ongoing limits in stamina, concentration, and day-to-day function.
A fast heartbeat and feeling unwell when upright can remain a long-term feature of postural orthostatic tachycardia syndrome due to NET deficiency. For many, this can mean needing to sit or lie down during routine tasks like waiting in line or taking a hot shower.
Ongoing tiredness can be one of the most limiting long-term effects, even after a full night of sleep. Some may find that exercise, school, work, or errands take much more energy than expected.
Trouble concentrating, slowed thinking, or short-term memory lapses may continue over time. People with postural orthostatic tachycardia syndrome due to NET deficiency may notice this most during reading, meetings, or multitasking, which can overlap with early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency.
Reduced stamina can last for years and may make physical activity harder to build or maintain. Over time, daily routines may shift around how long someone can stay upright without feeling worse.
How is it to live with Postural orthostatic tachycardia syndrome due to net deficiency?
Living with postural orthostatic tachycardia syndrome due to NET deficiency often means that simply standing up can set off a racing heart, dizziness, shakiness, fatigue, and mental fog, so everyday tasks like showering, standing in line, climbing stairs, or staying upright through school or work can take much more planning and energy. Many people living with this condition learn to pace activities, sit or lie down more often, and build routines around fluids, salt, medicines, and rest, because symptoms can flare from heat, long periods of standing, illness, or stress. It can also affect the people around you: family, friends, teachers, and coworkers may need to understand that someone can look well but still feel unwell, and practical support with transportation, schedules, or household tasks can make a real difference.
Treatment and drugs
Treatment for postural orthostatic tachycardia syndrome due to NET deficiency focuses on easing symptoms, improving daily function, and reducing the fast heart rate and dizziness that often happen when standing up. Many living with postural orthostatic tachycardia syndrome due to NET deficiency do best with a mix of fluids, extra salt when a doctor says it is safe, compression garments, gentle exercise, and avoiding triggers such as long periods of standing, heat, or dehydration. Doctors sometimes recommend a combination of lifestyle changes and drugs. Medicines may include drugs that help the body hold on to salt and water, tighten blood vessels, slow the heart rate, or support blood pressure, and the choice depends on which symptoms are most troublesome and whether other health conditions are present. Not every treatment works the same way for every person, so care is usually individualized and may need adjustment over time as symptoms change.
Can you cure Postural orthostatic tachycardia syndrome due to net deficiency?
No, there is not currently a cure for this rare inherited form of postural orthostatic tachycardia syndrome, or POTS, which causes the heart to race and can make people feel dizzy or faint when they stand up. Treatment focuses on managing symptoms with steps such as drinking more fluids, taking in more salt if a doctor advises it, wearing compression stockings, building up exercise slowly, and sometimes using medicines. Many people living with POTS can feel better with the right care plan, but doctors cannot yet reverse the root cause.
Non-drug treatment
Living with postural orthostatic tachycardia syndrome due to NET deficiency can make everyday things like standing in line, taking a hot shower, or walking upstairs feel draining. Non-drug treatment for postural orthostatic tachycardia syndrome due to NET deficiency usually aims to improve blood flow, reduce dizziness, and help you stay active more comfortably. Managing this condition often starts with steady daily habits and a plan tailored to what brings on symptoms.
Drinking more water and increasing salt, if your doctor says it is safe, can help your body hold onto fluid and support blood pressure when you stand. Many people with postural orthostatic tachycardia syndrome due to NET deficiency feel less lightheaded when hydration is spread through the day rather than taken all at once.
Waist-high compression stockings or abdominal binders can help keep blood from pooling in the legs and belly. This may ease dizziness, shakiness, and the racing heartbeat that often happens after standing.
A gradual exercise plan can improve stamina and help the body tolerate upright activity better over time. It often starts with seated, rowing, or recumbent cycling and then slowly builds, because not every approach works the same way for everyone.
Small physical moves such as leg crossing, calf tightening, or sitting down at the first sign of symptoms can help push blood back toward the heart. Standing up slowly and avoiding long periods of still standing may also reduce flare-ups.
Your genes may have an impact on how drugs work for you
For people living with postural orthostatic tachycardia syndrome linked to a shortage in the body’s norepinephrine transporter, inherited differences can change how strongly certain medicines affect heart rate, blood pressure, and dizziness when standing. In day-to-day life, this can mean one person feels much better on a small dose, while another gets side effects like feeling shaky, wired, or overly tired from the same treatment. This kind of gene-and-medicine matching, sometimes called pharmacogenomics, is not routine for most people with POTS, but it can help explain why response to treatment can vary so much.
Pharmacological treatments
Living with postural orthostatic tachycardia syndrome due to NET deficiency often means a racing heart, shakiness, or lightheadedness soon after standing, so medicines are chosen to calm those symptoms and make daily activity easier. There is no single drug approved just for this form of POTS, and treatment is usually tailored to the symptom pattern and blood pressure. Not everyone responds to the same medication in the same way, so doctors may adjust the plan over time.
Low-dose propranolol or metoprolol may help slow the heart rate and reduce pounding heartbeats when standing. These are often used when a fast pulse is one of the main problems in postural orthostatic tachycardia syndrome due to NET deficiency.
Ivabradine can lower heart rate without lowering blood pressure as much as some other medicines. It may be considered when rapid heartbeat remains a major symptom or when beta blockers are not well tolerated.
Clonidine or guanfacine may help in hyperadrenergic symptoms, such as tremor, surges of adrenaline-like feelings, or a marked rise in blood pressure on standing. This can be especially relevant when early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency include palpitations, anxiety-like feelings, and shakiness.
Fludrocortisone may help the body hold on to salt and water, which can support blood pressure and reduce dizziness in some people. Doctors usually monitor blood pressure and potassium because this medicine can cause fluid retention or low potassium.
Genetic influences
For many living with postural orthostatic tachycardia syndrome due to NET deficiency, the genetic link is direct rather than just a risk factor. This rare form is caused by changes in SLC6A2, the gene that makes NET, the norepinephrine transporter, which normally helps clear norepinephrine after nerves release it. When that transporter does not work properly, norepinephrine can stay active longer than it should, which can help drive the marked rise in heart rate and related symptoms that happen on standing. In reported families, this condition has been passed down in an autosomal dominant pattern, so one changed copy of the gene can be enough. DNA testing can sometimes identify these changes. That can help confirm how postural orthostatic tachycardia syndrome due to NET deficiency is inherited and give families clearer information about risks for relatives.
Is Postural orthostatic tachycardia syndrome due to net deficiency genetic?
Genetics are central in postural orthostatic tachycardia syndrome due to NET deficiency, because changes in the SLC6A2 gene can directly reduce norepinephrine transporter function. In some families, this inherited change helps explain early symptoms of postural orthostatic tachycardia syndrome.
Having a genetic risk is not necessarily a diagnosis
Gene variants are common and are a normal part of human biology. Most do not directly affect health and simply reflect natural human diversity. For many genes, having a variant associated with a condition points to a possible link rather than a definite diagnosis, especially when multiple genes and environmental factors play a role. In some situations, though, a single well-understood variant in a particular gene can be enough to confirm a diagnosis.
Pharmacogenetics—how genetics influence drug effects
Day to day, many living with postural orthostatic tachycardia syndrome due to NET deficiency may find that standing in line, taking a hot shower, or climbing stairs quickly brings on a racing heart, lightheadedness, and fatigue, so treatment often needs to be personalized. In this form of POTS, a gene change can affect the norepinephrine transporter, often shortened to NET, which normally helps clear norepinephrine after the body releases it. That helps explain how genetics affect treatment for postural orthostatic tachycardia syndrome due to NET deficiency: if this clearing step does not work well, medicines that raise norepinephrine or strongly stimulate the body’s stress-response system may worsen symptoms or need extra caution, while treatments that slow the heart, reduce these signals, or support blood volume may be more helpful. Genetics is only one factor, so doctors also look at blood pressure, hydration, other health conditions, and how someone has responded to past medicines before choosing treatment. In some families, genetic testing can help confirm the cause and guide safer medication choices, but it usually cannot predict exactly which drug will work best. Because response still varies from one person to another, follow-up matters, and doses are often adjusted slowly to balance symptom relief with side effects.
Interactions with other conditions
People living with postural orthostatic tachycardia syndrome due to NET deficiency may find that other conditions affecting the nerves, heart rate, or blood pressure can make daily symptoms harder to manage. For example, if someone also has dehydration, a viral illness, anemia, or a connective tissue condition, standing up may bring on more racing heartbeats, dizziness, shakiness, or near-fainting than usual. Doctors call it a “comorbidity” when two conditions occur together. Anxiety can also overlap, but it is important to know that postural orthostatic tachycardia syndrome due to NET deficiency is not simply caused by stress, even though the fast heart rate and lightheadedness can feel similar to a panic episode. Some medicines used for asthma, attention disorders, or depression may worsen symptoms because they can further raise norepinephrine levels or speed up the heart, so this matters when doctors look at the best treatment plan. If you are wondering about the early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency, it also helps to look for other illnesses happening at the same time, since they can blur the picture and change how severe the condition feels.
How genes can cause diseases
Humans have more than 20,000 genes, each carrying out one or a few specific functions in the body. One gene instructs the body to digest lactose from milk, another tells the body how to build strong bones and another prevents the body's cells from beginning to multiply uncontrollably and developing into cancer. As all of these genes combined are the building instructions for our body, a defect in one of these genes can have severe health consequences.
Through decades of genetic research, we know the genetic code of any healthy/functional human gene. We have also identified that in certain positions on a gene, some individuals may have a different genetic letter from the one you have. We call these hotspots "Genetic Variations" or "Variants" in short. In many cases, studies have been able to show that having the genetic letter "G" in the position makes you healthy, but having the letter "A" in the same position disrupts the gene function and causes a disease. Genopedia allows you to view these variants in genes and summarizes all that we know from scientific research, which genetic letters (Genotype) have good or bad consequences on your health or on your traits.
What other conditions can cause similar symptoms to Postural orthostatic tachycardia syndrome due to net deficiency?
Similar symptoms, such as a racing heart, dizziness, feeling faint, and tiredness when standing up, can also happen with dehydration, anemia, side effects from medicines, or an overactive thyroid. Doctors may also consider anxiety or panic attacks, heart rhythm problems, and other conditions that affect blood pressure or the body’s automatic nerve system, including other forms of POTS.
History
Throughout history, people have described feeling suddenly lightheaded, shaky, or faint after standing, even when routine tests did not show a clear heart problem. For many, this can mean needing to sit down after getting out of bed, feeling their heart race in the shower, or struggling to stand in a long grocery line. These symptoms were recognized long before doctors had a clear name for them.
As medical science evolved, doctors gradually separated these episodes from other causes of fainting and low blood pressure. In the late 20th century, the term postural orthostatic tachycardia syndrome, or POTS, became more widely used for a pattern of symptoms in which the heart rate rises too much on standing. Once considered rare, now recognized as a real and often disabling condition, POTS began to draw more research attention as clinicians noticed it affected daily life in ways that were easy to miss unless they asked the right questions.
A major step came in the early 2000s, when researchers described a small number of people with POTS who appeared to have a problem in the body’s norepinephrine transport system, sometimes called NET deficiency. Norepinephrine is a chemical messenger that helps control blood vessel tightening and heart rate when you stand up. When that system does not work properly, the heart may speed up more than it should, helping explain some cases of severe orthostatic symptoms.
Since then, POTS due to NET deficiency has remained an uncommon and specialized diagnosis within the broader POTS group. Not every early description was complete, yet together they built the foundation of today’s knowledge. Research later showed that POTS is not a single disorder with one cause, but a syndrome with several possible mechanisms, and NET deficiency is one of the best-known rare biologic explanations. That history matters because it helps explain why early symptoms of postural orthostatic tachycardia syndrome due to NET deficiency were sometimes dismissed, while today they are more likely to be recognized and investigated carefully.