The first thing that can and should be done is to carefully look for any of the signs of pain I've outlined earlier this month. This list is by no means complete, but it is a start. At the Princeton Animal Hospital / Carnegie Cat Clinic an evaluation of pain is part of every physical exam. With that said we are seeing your pet at a "snap shot" moment, and thus it is possible any ‘signs' are not currently visible. Your verbal history, especially as it reflects on the above list, is most helpful. Changes in your pet's behaviors should be carefully considered. Don't be fooled or explain away some of these signs like "Oh he's getting old."
Pain is treated best by a multimodal approach that addresses it at different levels along its path to the brain. Multimodal also refers to the fact that we typically use a combination of many techniques in an individual pet to tailor a plan specifically to them