I was diagnosed with high blood pressure a little over a week ago. I was put on an ace inhibitor (Coversyl Plus) but quickly went off it when I had an allergic reaction to it. My doctor then started me on Diovan HCT 160 mg. About four days after starting the Diovan I noticed that my heart rate was faster and "stronger" - I could really feel it beating. On Wednesday it was very rapid - 116 - so I went to see my doc. My blood pressure has come down and is now normal (I don't remember the readings). He sent me for an ECG which showed everything was normal except for the heart rate. He gave me Metoprolol 25 mg to help slow it down . Well, the last two nights I have been laying awake until 5 am - my heart is beating so fast. I'm supposed to see my doctor Tuesday but am wondering if I should go to the ER. From what I've been reading, this could be a side effect of diovan hct. How fast is too fast? Should I be overly concerned? Any advice would be greatly appreciated.