I went to the ER on Monday evening when my heart started irregular heart beat. That never happened before. I am 57 year old male with good health. No problems before and do not take any medications. They gave me a medicine to slow my heart rate and the next morning it got back in rhythm. Meanwhile I had several tests on my heart which showed no blockage or structural damage. As I left the hospital on Tuesday afternoon I was told to take a baby aspirin daily and I was given a prescription of Digoxin. After taking Digoxin for 4 days I felt terrible and weak and nervous and irritable and other things such as chest pain which I had not had and a terrible headache. On Saturday I decided to not take the medicine anymore and I will see my primary care tomorrow. I feel much better now. I believe that I was low on potassium and also the day of the heart issue I drank several more cups of coffee than usual. I never got to talk to a cardiologist. Any advice?