Your veterinarian will work with you to determine the best preventative care plan for your pet. Each patient is different in their needs and no two preventatives are the same. If you purchase preventives from sources other than a veterinary hospital, then you don’t have any guarantee that the products are authentic or that it has been stored and shipped properly. When you order from your veterinarian, you’ll have the added benefit of being able to rely on his or her expertise and knowledge of your pet’s medical history. Also, your veterinarian, typically, has exclusive rebates and discounts that the manufactures offer that can only be redeemed at the clinic. Plus, most of the preventatives are prescription only and must be prescribed by your veterinarian.