The Celadrin supplements that I got at Costco are terrific. I deal with knee pain all day, every day. The pain is not excruciating, but it definitely has been slowing me down. I am usually pretty conservative when it comes to adding any kind of vitamin, medication, or supplement to my day. I checked out Celadrin before I bought it and found out that it has not had any problems with side effects. I have been taking it now for over a month, and I do feel better and have less pain in my knees. This one is a keeper for sure! It seems as though the longer I take it, the better I feel I recommend this for anyone with joint pain.