supraventricular tachycardia
"My doctor prescribed me Metoprolol Succinate ER 25mg and advised me to take half first few days. When I did, I began to have a rush down my body and severe tremors began. My heart rate jumped to 138, it was pounding. I tried laying down, still. I even had chest pain. I usually get low blood pressure but I only felt very tired, not dizzy or fainty. I called my doctor, and he asked me to go to the ER to make sure everything is okay. I did. They did XRAY, blood work, gave me IV to flush it out. Everything was normal. My HR kept jumping from 67 to 105 suddenly. I was told to stop taking it. I am bummed out because I was looking forward to this helping me. After everything, my HR has was 54 resting and 72 active. It did afterwards!"