As far as I know there's only two kinds, the regular formula and the joint support formula. You give 1 teaspoon (its powder) for every 25 lbs, I mix it in Nebo's food. The bag says it is a 2 month supply for an average size dog. I've been giving it to Nebo (60 lbs) for almost a month and I have about half a bag left. It costs about $20-$25 per bag.