We've had our 10yo blue heeler on librela for over a year and it's been amazing. It takes 2 months to get max results but we noticed immediately that it was working. After being maxed, we tried waiting until we noticed her slowing down before giving another injection (made it 1 month and 24 days). That gave a baseline for how long we could go between doses, so we give every month and a half. I'm not kidding when I say we went from a dog we'd have to coax to keep up on an easy walk, to one who races off into the bushes for squirrels again. It definitely has made her life a lot more comfortable and, although it's expensive, it's been 110% worth seeing our old dog be young again.