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Hypovolema (and POTS?)



My CFS has always been very intwined with dysautonomia. While there have definitely periods when I've been in CFS states (total crashes) I've also had extended periods where it's really hard to tell where the CFS ends and the POTS begins. I've been healthy for a couple of years, but in April I started to have OI symptoms, and they've been going off and on with varying degrees of severity and disability since then. I was diagnosed (again) with POTS after a tilt in June, and everything that's been happening can--from a diagnostic standpoint--be explained by that, even some fatigue. (It's very convenient.) Except that nothing helps the POTS. For the last month or so my blood pressure has been low to extremely low, and I'm this curious off-white color.

So, my CFS doctor just suggested that it all might be hypovolema (low blood volume) instead of POTS--rather that while they are POTS symptoms, the mechanisms might be different. The Googles show there's a bit of a data on this in CFS (As much as there is on anything) and Dr. Bell's done some work on it. Does anyone have any thoughts or experience?


Hi Anne.

From my experience when I go to the bathroom too much - my POTS gets a lot worse.
This would make sense as if everything you drink comes out of you, your body stays less hydrated.

At my worst I would pass litres of fluid over night, and surprise surprise I was bed ridden in Hospital.
When this 'fixed' itself for reasons I will never know, I could gently begin to sometimes walk upright
gradually from room to rooom. Before I was totally incapacitated by heart problems, chest pain,
and blood pressure that was all over the place.

I had a urine test that checked for a hormone called Aldosterone
That was practically turned off.

POTS causes blood pooling, and so we'd need all the fluid we can get inside of us.
Yet if our body throws it out at an accelerated rate (many people with POTS find this), then it's
a losing battle that we fight.

POTS and CFS symptoms are practically identical. CFS patients have POTS, yet many people
with POTS don't have CFS. Or maybe they do?

CFS causes OI symptoms, it's a hallmark of the condition.

Have you had any blood work done? Sodium/Calcium? ADH (Antidieurtic hormone)?
Have you had a Urine Volume output measured?

You can do this yourself over a few days or even a week.
Measure everything you drink, and everything you pass.

Also you will know this, but in the summer people with POTS can
RETAIN water, due to a messed up Renin/Angiotensin/Vasopressein system
Often people find they can drink 2/3 Litres, and sometimes barely pass 700cc.

POTS people can drink 2.5 litres and output nearly 3.5L.
Randomly. All these things affect our blood volume.

Best thing I ever tried was a medication called MIDODRINE, and Vascular Tights that 'squeeze' your legs
and so, to a small degree, reduce blood pooling when standing/walking.

MIDODRINE (if tolerated) also leads to water retention as it affects the kidneys.
Last time I was on it, I'd be drinking by 9am and not visiting the bathroom sometimes for 12hrs later.

Check this out, it's quite interesing: