In my experience, it depends on what kind you were given, some are long acting-up to 6 wks., some are short acting and out of your system in a hurry. I **think** if I remember what my Dr. said, when I got an injection of solumedrol it was a short acting steroid, out of my system in a few days. Today I got an injection of Kenalog-40, I was told this is longer lasting. If you can remember the type/name of the shot, then maybe you can look it up online to see when it will take effect, and how long it will last.
