Postural Tachycardia Syndrome (POTS): Diagnosis and Treatment

What happens in POTS

When you stand, about 500 to 1,000 mL of blood shifts into the legs and abdomen. Normally, nerves tighten blood vessels and the heart rate rises by 10 to 20 beats per minute within seconds, keeping blood flowing to the brain. In POTS this adjustment is inadequate, so the heart compensates by beating much faster. The fast heart rate is a response, not the root problem. For a broad overview of symptoms and causes, see postural orthostatic tachycardia syndrome.

Common symptoms when upright

• lightheadedness, near-fainting and occasional fainting
• a pounding or racing heart
• fatigue, exercise intolerance, poor sleep
• brain fog and difficulty concentrating
• shakiness, sweating, nausea, headache
• blood pooling: purple, mottled feet and legs on standing

Symptoms worsen with heat, hot showers, large carbohydrate meals, alcohol, prolonged standing, dehydration and the premenstrual phase.

POTS subtypes

Many people have features of more than one. POTS is also associated with Ehlers-Danlos syndrome and joint hypermobility, autoimmune conditions, mast cell activation and chronic fatigue syndrome.

How POTS is diagnosed

Active stand test

This can be done in a clinic, and a doctor may ask you to repeat it at home with a blood pressure monitor:

1. Lie flat and rest for 5 to 10 minutes. Record heart rate and blood pressure.
2. Stand up and stay still, leaning only on your heels against a wall if needed.
3. Record heart rate and blood pressure at 1, 3, 5 and 10 minutes, and any symptoms.
4. Stop and sit or lie down if you feel faint.

A sustained heart rate rise of 30 bpm or more (40 or more in teenagers), usually above 120 bpm, without a drop in systolic blood pressure of 20 mmHg or more, supports POTS when symptoms have lasted 3 months.

Tilt table test

You lie on a table that tilts upright to about 70 degrees for up to 10 to 45 minutes while heart rate and blood pressure are monitored continuously. It is more controlled than a stand test and can also show vasovagal syncope or orthostatic hypotension, where blood pressure falls instead.

Tests to rule out other causes

• ECG, and sometimes a 24-hour heart monitor and echocardiogram
• blood count (anemia), thyroid function, electrolytes, glucose, cortisol if indicated
• review of medicines that raise heart rate or lower blood pressure
• assessment for dehydration, prolonged bed rest and deconditioning, which can produce similar findings
• inappropriate sinus tachycardia, in which the heart rate is high even lying down

Treatment plan

Treatment builds in steps. Non-drug measures help almost everyone and are continued even when medicines are added.

Step 1: Volume and salt

• Drink 2 to 3 liters of fluid a day. Drink 500 mL of water quickly before getting up in the morning or before standing for long.
• Increase salt to around 3 to 10 g of salt daily, through salty foods or salt tablets, only if your doctor agrees. This is not suitable for people with high blood pressure, heart failure or kidney disease.
• Electrolyte drinks can help, but watch the sugar content.

Step 2: Reduce pooling

• Compression: waist-high compression tights (20 to 30 mmHg or more) or an abdominal binder work better than knee-high socks.
• Counter-maneuvers: crossing legs, squeezing buttocks and thighs, clenching fists, or squatting when symptoms start.
• Raise the head of the bed by 10 to 15 cm (4 to 6 inches).
• Stand up slowly in stages, especially in the morning and after meals.

Step 3: Recumbent exercise program

Exercise reverses the deconditioning that worsens POTS, but must start lying or sitting down:

• Months 1 to 2: rowing machine, recumbent bike or swimming, 3 to 4 times a week, 20 to 30 minutes, plus leg and core strengthening.
• Months 2 to 3: lengthen sessions and add upright exercise gradually.
• Expect symptoms to feel worse at first; improvement usually appears after 4 to 8 weeks. Structured programs such as the Levine (CHOP) protocol have been studied in POTS.

Step 4: Diet and triggers

Eat smaller, more frequent meals with fewer refined carbohydrates; limit alcohol; avoid very hot showers and saunas; keep cool in hot weather.

Step 5: Medicines

No medicine is FDA-approved for POTS; all are used off-label and chosen by subtype:

• Low-dose propranolol or ivabradine: slow the heart rate.
• Fludrocortisone or desmopressin: increase blood volume.
• Midodrine: tightens blood vessels; taken during waking hours only.
• Pyridostigmine: improves nerve signaling to blood vessels.
• Clonidine or methyldopa: for hyperadrenergic POTS.
• IV saline is reserved for short-term rescue, not routine use.

Outlook

POTS is not life-threatening, though it can be disabling. Many people, particularly teenagers and those whose POTS followed a viral illness, improve substantially or recover within 2 to 5 years. Others have ongoing symptoms that are well controlled with the measures above. Pregnancy is generally possible; symptoms may change and should be discussed in advance.

Frequently asked questions

How is POTS diagnosed?

POTS is diagnosed with an active stand test or tilt table test showing a heart rate rise of at least 30 bpm (40 in teenagers) within 10 minutes of standing, without a significant blood pressure drop, plus at least 3 months of symptoms. Blood tests and an ECG rule out other causes.

Can I test for POTS at home?

You can do a simple stand test at home with a blood pressure monitor, recording heart rate lying down and then at 1, 3, 5 and 10 minutes standing. The results can guide your doctor but do not replace a formal assessment, which also excludes other causes.

How much salt and water should I have with POTS?

Most guidelines suggest 2 to 3 liters of fluid daily and, for many people, 3 to 10 g of salt a day. Salt loading is not safe for everyone, especially people with high blood pressure, heart or kidney disease, so check the amount with your doctor first.

What is the best exercise for POTS?

Start with recumbent exercise, such as a rowing machine, recumbent bike or swimming, plus leg and core strengthening. Build up over 2 to 3 months before adding upright exercise. Symptoms often worsen briefly at first, then improve after 4 to 8 weeks.

Can POTS go away?

Yes, for many people. Teenagers and those whose POTS started after an infection often improve over a few years. Even when it persists, most people see a meaningful improvement in symptoms with fluids, salt, compression, exercise and medicines.