I am a 39 year old female. I have been on Metoprolol ER 25MG bid for nearly 60 days. I quit smoking last Tuesday and my pulse is now staying in the 40's. I was placed on it to control sinus tachycardia, but I feel awful with my pulse this low. My GP seems unconcerned and I see a Cardiologist Thursday, but for the moment, I am quite concerned. I am tempted to simply go back to smoking and fix the balance of my body. With a pulse in the 40's I do not want to go into sudden arrest and die. I do not really have any symptoms of bradycardia but it remains frightening all the same. Any advice is greatly appreciated.