Brief Answer:
POTS maybe correct diagnosis

Detailed Answer:
Hello and welcome to Ask A Doctor service.

I have reviewed your query and here is my advice.

I carefully read your question. Unfortunately sometimes after viral infections PoTS syndrome can develop and it is most common in women of 15-50 years of age so it is likely that your doctor has this syndrome by what you describe. Other diagnosis could be chronic fatigue syndrome.

Very likely she should have gone through a thorough check with her doctor but just to mention that it is generally diagnosed with tests that confirm increase of the heart rate at least by 30 or above 120 per minute and this is done with tilt test, holter monitor of the pulse, etc.

It is also recommended to have some tests to rule out some other conditions like TSH and FT4 (to rule out problems with the thyroid) and CBC and ERS (to rule out problems with autoimmune disease), liver and kidney function tests (ALT, AST, Creatinine, electrolytes to rule out problems with these) and sugar blood tests as well.

If all the above come out normal but she gets increase of the heart rate at least by 30 while standing or it exceeds 120 then the diagnosis of POTS syndrome is very likely.

Unfortunately there is no standard treatment for POTS but there is some things that might help:
- drinking plenty of fluids and increasing the salt intake
- taking frequent small meals during the day (5-6 small meals instead of 2-3 big ones)
- having a good combination and balance of protein, carbs and fat in diet during the meals
- lifting the head of the bed a little (by putting some bricks under the bed feet at the head of the bed, not by adding pillows as this might cause problems with the neck) so she does not stand directly from fully horizontal to vertical position
- standing in stages and slowly and not immediately and abruptly
- if she gets the symptoms and can not lay she can try to cross her legs in front of her while standing, contracting the muscles of the legs, buttocks and fists and try to move the legs so the blood is pumped up.
- she can wear compression stockings that will not allow the blood to be pulled in her legs
- even though POTS causes fatigue it is recommended that she tries to do regular exercise even though it might be mild, this will help her keep active and with time she might improve the amount of exercise she does

Unfortunately there is no licensed drug to treat POTS (not enough studies to confirm their effect) but there are drugs that doctors believe can help with the symptoms of POTS like:
- a beta blocker which can prevent the heart from racing (ivabradine)
- midodrine which keeps the blood vessels narrow
- fludrocortisone which helps keep water and salt in the body
- SSRI which are antidepressants that affects the central nervous system

Even though POTS can be very distressing with the fatigue and the rest of the symptoms as it is happening with your daughter, the good news is that generally POTS disappears in a few years and she will not need to live with it all her life. The above measures and treatments can help her cope a bit better with it and handle daily activities.

I hope I have answered your questions. Please let me know if I can assist you further.

Kind regards,

Antoneta Zotaj, General and Family Physician

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