Is Taking Prednisone Safe Before Bariatric Bypass?

3 days ago I started itching at my arm on the inside of my elbow. The itch was intense. I went to my doctors and she looked at the rash, it s been a few days since the on set and it was spreading. As of now it is on both legs (shin area) about 3 in diameter, across my chest, my belly, neck. The doctor said she didn t know what caused the rash or what type of rash it is. She prescribed Prednisone 3 - 10mg tablets - to be taken for 5 days. It appears to getting worse. My main concern right now what can I do, as I am scheduled for a bariatric bypass on Monday march 16. at a time f