you can use glucoseamine, chondritin and MSM together, you'll have no problems. Keep in mind that G and C should be used together as they are more effective that way. Liquid form is also easier to absorb then powder. All these products do esstenially is increse the amount of fluid in the joint, they don't repair damage, so after being on them and once your loading period is done you may find your animals joints swell so adjust the dose accordingly.