What Is Postural Orthostatic Tachycardia Syndrome?
Postural orthostatic tachycardia syndrome (POTS) is a disorder in which most of your blood stays in your lower body when you stand up, and in response, your heart rate jumps.
Your blood usually flows at a steady rate whether you're sitting, standing, lying down, or hanging upside-down from a tree branch in the backyard. But if that rate changes when you change positions, that’s a condition called orthostatic intolerance (OI). It’s the most common symptom of POTS. It can make you feel dizzy, lightheaded, or faint.
POTS makes your heart beat faster to try to get blood to your brain. Your heart rate can go up by 30 beats or more a minute after you stand. As that happens, your blood pressure is likely to drop.
POTS can throw your whole body off balance. You might have:
- Dizziness or fainting
- Blurry vision
- Belly pain
- Diarrhea or constipation
- Severe sweating
- Brain fog
- Extreme fatigue
- Blurry vision
- Higher or lower blood pressure
- Faster or slower heartbeat
- Chest pain
- Feeling hot or cold
- Feeling anxious, nervous, or jittery
- Shaking or tremors
- Headaches, body aches, or neck pain
- Unusual color in hands and feet
You might be more likely to notice these when you're in the shower, standing in line, or feeling stressed. You also may have POTS symptoms after you eat because your intestines need more blood for digestion.
Types of POTS
POTS can happen for different reasons. You could have more than one kind. Some of the most common are:
- Neuropathic. You have damage to small fiber nerves that manage blood flow in your limbs and abdomen.
- Hyperadrenergic. You have higher levels of the stress hormone norepinephrine.
- Hypovolemic. You have unusually low blood levels.
POTS Causes and Risk Factors
Women between 15 and 50 years old are more likely to have POTS. It can run in families, but researchers haven’t identified a single gene that might be linked to the condition.
Several diseases and conditions seem to make you more likely to have POTS. These include:
- Anemia (when you don’t have enough red blood cells)
- Autoimmune diseases, like Sjogren’s syndrome or lupus
- Chronic fatigue syndrome
- Diabetes and prediabetes
- Ehlers-Danlos, a muscle and joint condition
- Illnesses like mononucleosis, Lyme disease, or hepatitis C
- Multiple sclerosis
- Click-murmur syndrome (also called mitral valve prolapse)
It can also happen after a serious infection, pregnancy, or a head injury.
With such different symptoms, POTS can be hard to diagnose. A tilt-table test may be the best way to test for it.
Your doctor will ask you to lie flat on a table and strap you in so you won’t fall when it tilts. The table slowly moves your body upright to simulate standing up. Your doctor will watch for changes in your heart rate.
Some people who have POTS may faint during this test. It’s important to work with a doctor who’s very familiar with the condition. This might be a heart doctor (cardiologist) or a doctor who specializes in problems with your nerves and muscles (neuromuscular specialist).
Your doctor might also order other tests, including:
- Urine tests to measure your sodium levels and rule out other causes of your symptoms
- Blood tests to check your kidneys, liver, and thyroid gland and to rule out other causes
- EKG and echocardiogram to see how well your heart is working
- Quantitative sudomotor axon reflex test (QSART) to test the nerves that control sweating
- Valsava maneuver to check the nerves that control your heart. You breathe out strongly through your mouth while holding your nose closed.
- Autonomic breathing test to measure your blood flow and pressure during exercise
- Biopsy of your skin nerves. Your doctor will take a tiny sample for analysis under a microscope.
There's no cure for POTS, but treatment can help with your symptoms.
- Medication. Your doctor may prescribe drugs such as fludrocortisone (along with more salt and water), midodrine, phenylephrine, or a type of medicine called a beta-blocker to help with blood flow.
- Compression stockings. These help push the blood up from your legs to your heart. You’ll want ones that provide at least 30 to 40 minutes of compression and go all the way up to your waist, or at least up to your thighs. Your doctor can prescribe a pair.
- Diet. Salt and water are key. They keep fluids in your body and raise the amount of blood in your body. Think pickles, olives, nuts, and salted broths. Eat smaller meals more often with a healthy balance of protein, vegetables, fruits, and dairy.
- Exercise. POTS can make it hard to be active, but even light exercise such as walking or simple yoga can help with blood flow and keep your heart healthy.
- Lifestyle. If you get tired easily, you may not always have the energy to take care of yourself. Learn how to take your pulse and blood pressure. Ask your doctor what your numbers should be, and check them regularly.
- Sleep. Try to stick to a sleep schedule. You also might raise the head of your bed to make it easier to stand up after lying down.
- Communication. POTS can make simple activities a bit harder, and that can be frustrating and stressful. A support group or therapist may help you manage the emotional issues the condition can cause.