Cosequin DS Double Strength Plus MSM Joint Health Supplement is for dogs of all sizes. Cosequin plays an important role in maintaining optimal joint function. Healthy articular (joint) cartilage is crucial to joint utility. Cosequin helps support cartilage production and protect existing cartilage from breakdown. Cosequin is the only glucosamine/chondroitin sulfate supplement that has been shown safe, effective, and bioavailable in peer-reviewed, published, controlled, U.S. veterinary studies. Cosequin is manufactured following standards similar to those practiced by the pharmaceutical industry.