My Dr. prescribed propanenone hydrochloride extended release capsules 325 mg two times per day. I have A Fib which goes back to sinus, at the longest period, has been about 10 minutes, usually closer to 2. My heart muscle is strong, my valves are strong, my arteries look good, I have had no stroke or heart attacks, I have normal blood pressure and do not have diabetes. I am 55 years old and am a female. I was wondering if I should ask him about a blood thinner or a lower dose to begin with? It seems as from everything I have read there is some concern with this drug, but if it works, I don t have to worry about any surgeries. what do you think