POTS, or postural orthostatic tachycardia syndrome, is a condition where your heart rate spikes abnormally when you stand up. In adults, the defining feature is a heart rate increase of more than 30 beats per minute (or a rate exceeding 120 BPM) within 10 minutes of standing. For adolescents, the threshold is higher: at least 40 beats per minute. An estimated 500,000 to 3 million people in the United States live with POTS, and it affects women roughly five times more often than men.
What Happens in Your Body
When a healthy person stands up, gravity pulls about half a liter of blood into the legs and abdomen. The nervous system detects this shift almost instantly and compensates by tightening blood vessels and gently increasing heart rate, keeping blood flowing to the brain without you noticing a thing.
In POTS, that compensation goes wrong. Blood pools in the lower body, reducing the amount returning to the heart. Each heartbeat pumps less blood, and the brain’s pressure sensors detect the shortfall. In response, the nervous system ramps up heart rate aggressively to make up for the lost volume. Women are particularly susceptible because they naturally have smaller stroke volumes (less blood pumped per beat) than men, so any further drop hits harder. The result is a racing heart, but often without the significant blood pressure drop you’d see with simple fainting.
Why POTS Develops
POTS rarely appears out of nowhere. Common triggers include viral infections (Epstein-Barr virus, influenza, hepatitis C, and COVID-19 are all documented), physical trauma, major surgery, pregnancy, and periods of prolonged stress. Vaccines have also been reported as triggers in rare cases. In many people, the condition develops after a combination of these stressors, and some cases have an autoimmune basis where the body’s immune system interferes with normal nerve signaling.
The Three Main Subtypes
Not everyone with POTS has the same underlying problem. Doctors generally recognize three overlapping patterns.
Neuropathic POTS
This is the most common form. The sympathetic nerves that control blood vessels in the legs and kidneys are partially damaged in a patchy pattern. Without proper nerve signals telling those vessels to tighten, blood pools in the lower body when you stand. The damaged kidney nerves also reduce the hormones that help your body retain salt and water, which compounds the problem by lowering overall blood volume.
Hyperadrenergic POTS
In this subtype, the brain sends out excessive “fight or flight” signals. People with this form often have very high levels of norepinephrine (a stress hormone) when standing, sometimes two to three times the level needed for a basic POTS diagnosis. Blood pressure may actually spike on standing rather than stay stable, and symptoms like tremor, anxiety, and flushing tend to be more prominent.
Hypovolemic POTS
Some people with POTS simply don’t have enough blood volume. When they stand, there’s not enough circulating fluid to reach the brain, and the heart races dramatically to compensate. These patients are more likely to also experience drops in blood pressure and may feel worst after sweating heavily, skipping fluids, or spending time in heat.
Symptoms Beyond a Fast Heart Rate
The racing heart gets the most attention, but POTS is a whole-body condition. The most commonly reported symptoms include palpitations, fatigue, lightheadedness, exercise intolerance, nausea, difficulty concentrating (often called “brain fog”), trembling, and fainting or near-fainting episodes. Many people also experience disrupted sweating and temperature regulation, meaning they overheat easily or sweat unpredictably. Bowel and bladder problems, including bloating, constipation, and urinary frequency, are also common because the autonomic nervous system controls those functions too.
Fatigue is often the most disabling symptom. It’s not ordinary tiredness. People with POTS describe it as a deep, unrelenting exhaustion that doesn’t improve with sleep. Combined with brain fog, it can make work, school, and daily tasks genuinely difficult.
How POTS Is Diagnosed
The primary diagnostic tool is a tilt table test. You lie flat on a padded table with straps holding you in place. Electrodes on your chest monitor heart rhythm, a cuff tracks blood pressure, and a fingertip sensor measures oxygen levels. After about five minutes lying flat to establish your baseline, the table tilts upward to simulate standing. You stay in that position for anywhere from 5 to 45 minutes while the team watches your heart rate and blood pressure response.
If your heart rate climbs more than 30 BPM (40 in adolescents) without a major drop in blood pressure, that pattern points toward POTS rather than orthostatic hypotension, where blood pressure itself falls significantly. Some doctors use a simpler “standing test” in the office: you lie down, then stand, and your vitals are tracked over 10 minutes. The tilt table version is more controlled, but both look for the same heart rate pattern.
Daily Management Strategies
The foundation of POTS management is expanding blood volume and reducing pooling. Current guidelines recommend 10 to 12 grams of sodium per day (far more than a typical diet) and 2 to 3 liters of water. This combination helps the body hold onto fluid and keeps blood volume higher. Compression garments that reach at least up to the belly button are more effective than knee-high stockings, because they compress the large veins in the abdomen and thighs where the most pooling occurs. Sleeping with the head of the bed elevated to about a 30-degree angle can also help by training the body to retain fluid overnight.
Exercise is one of the most effective long-term treatments, though it’s also one of the hardest to start. Because standing exercise triggers symptoms, many people begin with recumbent activities like rowing, swimming, or reclined cycling. Over weeks to months, a gradual reconditioning program can improve the heart’s ability to pump blood and reduce resting heart rate, which lowers the spike that happens on standing.
Medications That Help
When lifestyle changes aren’t enough, several types of medication target different parts of the problem. For heart rate control, beta blockers slow the heart directly, and another option works specifically on the heart’s natural pacemaker cells to reduce rate without affecting blood pressure. For blood pooling, a medication that tightens blood vessels in the limbs increases resistance and pushes blood back toward the core. Another option improves nerve signaling in the autonomic system, reducing pooling indirectly.
For low blood volume, a medication that helps the kidneys retain sodium and water can raise circulating fluid levels over time. In severe flares, intravenous saline infusions provide rapid relief by directly expanding blood volume. No single medication works for everyone, and most people with POTS use a combination of approaches tailored to whichever subtype and symptoms dominate their case.
Who Gets POTS and What to Expect
POTS most commonly appears between the ages of 15 and 50, with a strong peak in the teens and twenties. The 5:1 female-to-male ratio is one of the most striking features of the condition, and researchers believe hormonal differences, smaller blood volumes, and differences in vascular tone all contribute. In large surveys, women make up roughly 94% of the patient population.
The trajectory varies widely. Some people, especially those whose POTS started after a viral illness, improve significantly within one to three years. Others have a more chronic course that requires ongoing management. The condition is not life-threatening, but its impact on quality of life can be severe. Many patients cycle through multiple doctors before getting a diagnosis, partly because the symptoms overlap with anxiety, dehydration, and other common conditions. Awareness has grown substantially in recent years, particularly after COVID-19 brought post-viral autonomic dysfunction into wider public conversation.