It should be available next to the glucosamine/chondroitin supplements. It has been shown to help joints and connective tissue. As with all of these joint supplements, I would try one at a time for about six months, then go off of it. If you notice a difference in pain in any of your joints, the supplement may have been helping.
Or you can do all supplements at once (glucosamine/chondroitin, SAM-e, MSM). Do them for like six months. Then stop doing only one of them. Use a process of elimination to see which ones work best for you.