I take Metoprolol. They started me on a really, really low dosage. It was like a miracle drug. I had constant tremor, severe nausea and headaches, severe orthostatic tachycardia (resting heart rate was 40, standing would go up to 180 and into the 200's), I couldn't stand up, was constantly blacking out. I now take 50 mg twice a day. They tried to reduce it to 75 mg per day but caused symptoms to exacerbate. My blood pressure went too low (90/50) so they added a small dose of Midodrine and it's helped. I still have bad days where I feel really lousy, but my functioning is pretty darn good now. I can now go for walks, bike rides, and have been able to start some light weight training.