I had a cortisone shot in my left knee last May in attempts to help my ITBS. The shot itself did not hurt at all (I was shocked!) but about 1-2 hours later, the pain came on strong. I rested for 5 days, per ortho doc orders, and then eased back into my cycling routine. Felt minimal relief from the discomfort the IT band was causing during that resting period. Once I started becoming active again the discomfort returned to the same levels as before the shot.