Two things came to mind when I read your post. One is that you had been regularly exercising and had to abruptly stop. This, along with beta blockers can cause several of the symptoms that you are describing. How long have you been on the same beta blocker? Have they considered trying a different one? I'm glad to hear that you are starting to be able to exercise again . I think this will only help you! Also, have you always had supine hypertension? Your blood pressure when you are standing up is actually very healthy and normal, but you should NOT have hypertension while lying down. This puts you at risk for a variety of things including ventricular hypertrophy--enlarged heart--which can cause further arrhythmias. Have they evaluated you on an event recorder? (monitor worn for a month). The "head rushes" you are describing could easily be from premature ventricular contractions (PVC's). I experience the same feeling when I get PVC's, and beta blockers actually increased them (although usually for other people this is not the case). I really feel your pain because I am dealing with arrhythmias in addition to POTS also. I had an EP study but they did not end up doing an ablation (which I have mixed feelings about), so I still have my SVT. I hope that things will continue to improve for you and that they will be able to find the right medications to help you! I personally felt HORRIBLE on beta blockers, but I also have MCA and apparently cannot tolerate them. I know that for the normal person beta blockers can take a while to get used to (about a month in most cases). If you have been on the same beta blocker for longer than that and still have horrible symptoms, I would mention it to your cardiologist because he may he able to switch you to something more agreeable .