I am 40 years old & I'm on Atenolol for tachycardia. Because of fluid intake my doctor put me on Triamterene a year ago. I have been extremely tired, no energy at all. I feel at times that I could just sleep for days. The fatigue gets worse as the day goes on. I checked my BP yesterday and at 2:05pm it was 77/56, pulse 83 at 2:09 96/52, pulse 80 at 3:39pm 100/59, pulse 80 & at 4:45pm 92/52, pulse 65. This morning at 9:12am it was 97/55, pulse 83. Is it too low or am I just imagining things.