Am on zytiga and xgiva for metastasized bone cancer following prostate. have been on it for a year. Have noticed increasing fatigue (to be expected on these drugs), dizziness and lightheadedness. Have passed out twice. On going to emergency yesterday was checked to make sure no heart attack, told them drugs I was on, and was given SDZ Bisoprolol to lower blood pressure and regulate heart. They diagnosed me with atrial fibrillation. I am already on Coversyl for bp. Take blood pressure regularly, it vacillates from 147/96 to 118/73 in a matter of minutes. pulse very rapid with mixed beats. my question is, will taking bisoprolol make my dizziness and fainting increase?