Hi, I have gone through your question and understand your concerns. Since you have been taking Bystolic for 1 year and half, these are not side effects from taking this medication. All the above symptoms might be due to discontinuing Bystolic and experiencing the withdrawal syndrome . I assume you were taking Bystolic, a beta blocker medication, for being diagnosed with HTN (hypertension). This medication works by lowering your heart rate and automatically your blood pressure. When your body does not have this medication for more than 2 days, it starts increasing your heart rate ( tachycardia) and rebound hypertension develops. The symptoms of rebound hypertension are: 1. Anxiety 2. Shortness of breath 3. Chest tightness 4. Nervousness, headaches 5. Dizziness 6. Malaise, nausea, loss of appetite 7. Insomnia etc If you were my patient : 1. I would measure your BP and if it s above 140/90 i will start you on another antihypertensive medication, such Enalapril or Losartan ( ACE-Inhibitors/ARBs ) based on guidelines for your age (2.I will get a CBC, UA ( urine analysis) BUN/Crea ( check for kidney function) and measure the levels of your electrolytes Na, K, CL, HCO3. 3. Have a baseline EKG and /or Cardiac Echo to check the heart structure and function. I would advise you to go back to your doctor and do the above testings. Do not delay, because Xanax will not treat your HTN. I hope this is helpful and I have answered your question. Please let me know if i can assist you further. Kind Regards, Dr. Ledia Qatipi General & Family Physician