irregular heart beat. I m currently on day 7 of prednisone. 40mg, 40, 40, 30, 30, 30, 20 today. I have had an irregular heartbeat for the last few hours. Do I need to worry about it now or can I wait to call my dr tomorrow since they re closed? I m otherwise healthy. This is my first time on Prednisone. Another side effect is not being able to sleep, so I also wonder if the irregular heartbeat is simply caused by me being overtired. I m 38 year old female, 5 1 , 103 lbs.