Diclofenac was approved in the US for OTC sales not too long ago. Big Brand Name: Voltaren. I know some people helped by the cream form. Don’t know what the pills side affects are.
Diclofenac is basically just another NSAID, like ibuprofen, naproxen, meloxicam, sulindac, indomethacin, ketoprofen, and dozens of others. No single NSAID has been shown to be better than another for pain relief across the board, though individuals do respond differently to different ones.
Topical NSAIDS like diclofenac and ketoprofen do seem to offer some additional relief, but only about 10% of patients get additional relief over placebo.