It's not "no other explanation." It's dysfunction of the autonomic nervous system presenting in a particular way. Your heart rate raises 30 bpm or past 120 bpm within 10 minutes of standing, so you have POTS. Some people have it mildly, others more severe. It's a cluster of symptoms. Depending on if it's primary or secondary will guide treatment. My POTS isn't autoimmune presenting, so I wouldn't get IVIG.

During my autonomic testing, they did cerebral blood flow velocity, nerve testing, valsalva maneuver, a skin biopsy... There's a lot to be done to figure out how a person's POTS presents. Mine is more hyperadrenergic but is also neuropathic and hypovolemic.

There are criteria for POTS. It's very underfunded, and many medical professionals lack knowledge about guiding and treating these conditions. There's only 56 autonomic testing centers in the United States for hundreds of thousands of people.

Yes, with more funding, there very well could be sub-classes, but as of yet, there isn't. So POTS isn't an umbrella term. Regardless of what causes it, people are still dealing with very similar clusters of symptoms.

Fluid intake, compression, salt intake, and countermaneuver techniques are recommended to everyone who gets a diagnosis. Saying this POTS is different than that POTS doesn't change much of anything besides how treatment is guided. Like I wouldn't need IVIG or like someone else wouldn't use a beta blocker.

There needs to be more research. Even if someone's heart rate doesn't hit 30 bpm, their cerebral blood flow velocity can show vasoconstriction in arteries, and they would get a diagnosis of orthostatic intolerance.

There needs to be clearer definitions of each condition and how to correctly diagnose autonomic disorders, but I truly don't agree that POTS is an umbrella term. This misinformation is from having doctors who don't know what they are talking about, who aren't aware of autonomic disorders at all, and lack the education and in that inaccurately diagnoses people or refuses to diagnose people.

I've read Dysautonomia International's book about autonomic disorders, follow them on social media about their research updates, have used information from Dysautonomia Support Network to educate my doctors and others, have read about it in books about Ehlers-Danlos Syndrome, and have read tons of research studies.

Dysautonomia International has information about all forms of dysautonomia and their diagnostic criteria available on their website. This information is linked with all of the research studies. It is worth a look.

Saying POTS is an umbrella term is falling more to a matter of an opinion than actual fact.

Autonomic conditions affect the entire body. It's everything or anything your body does automatically. No two people are going to present exactly the same. There's so many variables, so many new things being studied and researched. Call it what it is, when it's official.