what kind of arthritis meds? my 3 year old dog have arthritus (sp?)
My dog seems to be tolerating carprofen pills well. Ask your vet about getting a baseline done before starting the drug so you'll have something to which to compare later organ function tests. Btw, urine analysis is a more sensitive detector of kidney dysfunction then blood, so I'm not sure if a pre-drug baseline is useful there.
I also mix in fish oil with his food and, most importantly, moderate his exercise (intensity and duration). Weight loss is essential if your dog is overweight.
Some people like cartrophen injections (sounds similar but a totally different drug than carprofen) for osteoarthritis so you could look into that too, but I noticed no difference with it.
Btw, be sure to confirm that it's arthritis and not an injury like an ACL tear.