I don't have POTS as a rule, but NMH. (However if my life depended on rushing or trying to run, especially in the morning, I could, or have, suddenly gone into that very unpleasant heart-pounding over-reaction of the body trying to get some circulation going.) I did feel a sort of physical anxiety with 3 capsules of the Nature's Way Butcher's Broom on top of the Midodrine. But since I am still experimenting to see if this herb can have some value in my case, today I am taking 1 capsule on top of Midodrine, and it feels: so far, so good.