I have been cracking my knee since I was in grade school. It used to bother me most at night but as I have grown older (61 now), it is intolerable. I can't fall asleep because of the need to crack my knee. 1000mg of asprin used to be the only thing that would relieve the pressure but can't take it any more because of my stomach. I recently had surgery and I find that 1/2 table of vicodin gives me the relief in order to fall asleep. I'm running out of this medicine and have made an apt with a doctor to see what he will perscribe. This is an every night occurrence now.