The Royal Canin Veterinary Diet Calm formula is designed for cats. It include two amino acids that help pets maintain emotional balance. Alpha-casozepine is an amino acid chain derived from milk shown to have calming effects. L-tryptophan  is a more commonly known amino acid that also has calming effects. In addition, the formulas include Nicotinamide, also known as Vitamin B3. Nicotinamide creates a calming effect within the central nervous system. Key Benefits Feline Calm is a highly digestible, palatable, complete and balanced adult cat food formulated to meet the nutritional needs of cats facing digestive, skin and urinary sensitivities. Formula contains calming effects from Alpha-casozepine, L-tryptophan and Nicotinamide (Vitamin B), optimal amounts of these B vitamins and amino acids help maintain the skin's natural barrier effect S/O index Promotes a urinary environment unfavorable to the development of both struvite and calcium oxalate crystals Contains a specific nutrient blend to help regulate intestinal transit and to help support beneficial digestive flora The combination of fibers in this diet encourages normal intestinal transit and the elimination of hairballs in stoolsRoyal Canin