The main difference between Ultamino and HP lies in the source of the protein used. Ultamino primarily uses hydrolyzed animal protein as the protein source, while HP uses hydrolyzed soy protein. The choice of protein source can depend on the individual dog's specific dietary needs and any known allergies or sensitivities. Royal Canin Ultamino is a prescription diet formulated for dogs with severe food sensitivities or allergies. It is specifically designed to be highly digestible and contains a limited number of proteins to minimize the risk of triggering an allergic reaction. The proteins used in Ultamino are broken down into tiny molecules called peptides, which are less likely to provoke an immune response in dogs with sensitive digestive systems. Ultamino may also include highly digestible carbohydrates and specialized nutrients to support digestion and overall health. Royal Canin HP (Hypoallergenic) is another prescription diet intended for dogs with food sensitivities or allergies. Like Ultamino, HP is formulated with a limited number of ingredients to minimize the risk of triggering an allergic reaction. It uses hydrolyzed soy protein, where the protein is broken down into small, easily digestible molecules to reduce the chances of an immune response. HP is also formulated to support skin and coat health, as these are often affected by food allergies or sensitivities. Additionally, it may contain specific nutrients to support digestive function and the overall well-being of the dog.