Hey, here is my experience.
The barn I manage has a 23 year old mare that was in terrible pain about a year ago. She was on bute, could barely walk, arthritis. We tried shoes, which she still has on. We switched her to previcox, as well as the bute for a while, took about two months to see a difference. We then took her off bute about 3 months after putting her on previcox.
I'm not saying previcox will work for everyone, but I am seeing a huge difference in her movement. She trots and even gives little canters once and a while. Yes she has her off days.
I would definitely try the previcox before injections, what is there to lose?
Skutter - BelgianX born: May 28 2009
Spring - Standardbred born: May 2005