Pain
"I used Voltaren gel on some sore joints (and a tennis elbow). It worked as well as anything I have ever tried. I sometimes get killer tension headaches that first build up in the back of the neck.  When I felt one coming on, I used the gel on the back of the neck and shoulders.  The headache never developed.  Before this experiment I would take 3 or 4 ibuprofen for one of these headaches and hope for the best.  The gel is now my standard treatment for these headaches."