On the average day, before I started the beta blocker, my HR was going into the 160's and 170's and nothing was stopping it.
Before treatment of my thyroid and adrenals I used to have extremely low bp to the point of extreme dizziness/blackness and I am sure then all I could tolerate would be 10 mg but I still needed it or my heart would go crazy upon exertion.
I still only take 10 mg twice daily of Propananol and it means I hardly know I still have POTS but that is until I go into a store where the heating is always too much for me plus standing and then it comes back pretty quickly and I have to get out because my legs get so heavy and feel like they won't hold me up any longer. After that I need a good lie down and use my oxygen concentrator for 30 minutes in order to recover. That way it can stop me getting PEM.
Pam