Cosequin Maximum Strength Plus MSM contains glucosamine hydrochloride, sodium chondroitin sulfate, and methylsulfonylmethane (MSM). This combination of ingredients help support healthy cartilage. Cosequin joint health supplements are brought to you by Nutramax Laboratories Veterinary Sciences, the #1 veterinarian recommended supplement company. ▼Source: Among retail brands. Survey conducted among small animal veterinarians who recommended oral joint health supplements. *Source: Survey conducted among small animal veterinarians who recommended animal supplements.