Mary (Medusa) gives Clomicalm glowing reviews. It has usually been used in dogs, but is successful with cats.

Nancy Efrusy is a pet psychic who has done some wonderful work for PTrs. She isn't in it for the money. Her email addy is efrusy at yahoo.com

I guess Diego doesn't have chronic pain? But he has been like this ever since the fire, right?

Many prayers being sent!

ETA: It struck me that adding another male cat might be an idea...I'm not kidding. Another male would be able to give as good as he gets, and draw some lines. Hard to explain the hunch...but I knew that having a female cat added to my home would work out fine.