This is really interesting, according to declassified CIA Documents, there is a method you can use to make pain disappear.
According to the document:
TO REDUCE PAIN SIGNALS: Look with your closed eyes at the part of your body which is the source of pain signals. As you look, repeat in your mind the number 55515. When you do these two things, the pain signals will slowly reduce until they are no longer important.
The document also explains how to reduce emotional charge, to balance any part of the body, and more.