I have had two ESI injections In November 2011 within 13 days of each other. After the second injection I gained 10 pounds within a week, I am 120 pounds and have been consistent with that for 20 years and before that I weighed less. I am 5 6 and 46 years old with exercise as part of my life. I have always had a fast matabolism but since this injection I cannot get the 10 pounds off, not even one ounce. How long does this cortisone injections last in your body and what has it done to my metabolism?