
Hi Goldie,
I have just replied on your other thread, before seeing this one. Devils claw is anti inflammatory and pain relief, so if it works for her it could substitute for pain killer. I think synoquin is a joint supplement helping to maintain cartilage, which you would continue to give. You could also give the Devils Claw with the pain killers, but perhaps reducing the pain killers.
My dog has her pain killers (lower than recommended) plus Devils Claw, and it seems to give an extra boost. I believe the trick is to reduce the painkillers and add the Devils Claw, and change the combination until you find the levels that work for her. Caprodyl used to be Rimadyl I think, which I used for years on my previous dog.
If you are in any doubt, ring your vet and ask if it will be OK.