Hi, thank you for your time. My Mom is 92, has a-fib, fluctuating blood pressure and a pace maker. Her cardiologist, primary and nurse all have different recommendations on her most recent medication; Metoprolol Succinate 50 mg. One recommends 2 x day, one recommends 1 x day and the other recommends 1/2 twice a day. I m not sure which quantity and frequency would be best....please advise. Thanks, Elizabeth