Hi. In January I got a really bad cold and was prescribed antibiotics, Flonase , and Mucinex DM. Two doses later I woke up to go to work and my pupils were enlarged, I was pale, and my heart was pounding. I went to the er with a heart rate of 156. This sparked my anxiety and panic and I ve been dizzy, lightheaded, fatigued, blurry vision , short of breath, and heart palpitations pretty regularly since. I went to the er again in April not having taken any medicine with a heart rate of 136 and again yesterday after I felt my heart pop and then the panic sensation and heart pounding. It was only around 110 this time, but I could not slow it. The doctors say this is all anxiety/panic. I ve had ekgs, worn a holter monitor , and even seen a endocrinologist . When the heart pounding, flutters, or jumping happens I am always at rest. Do you believe this is just panic? And when should I really worry when my heart is pounding?