Nutramax Dasuquin has avocado/soybean unsaponifiables (ASU) in it, whereas Nutramax Cosequin doesn't. That said, Dasuquin costs more. According to reviews, one does not seem to be better than the other, except for the price difference. Dasuquin ultimately would be more ideal for dogs who suffer severe situations such as the case of hip and elbow dysplasia and arthritis. Both Nutramax Cosequin and Dasuquin are great supplements. Both of these are dog joint supplements created by the same company, Nutramax Labs. As to how they are similar, they both contain MSM, glucosamine, and chondroitin.