The Feliway diffuser offers constant comfort and calming at home. Studies have shown that the use of Feliway is 90% effective* in helping reduce or eliminate scratching and urine spraying. A significant reduction in these behaviours is usually seen within 7 days. You can replace the vials every month by buying a FELIWAY Refill. The diffuser should be checked monthly and replaced every six months to ensure optimum effect. Urine marking, Vertical scratching, Loss of appetite, Avoidance of Social Contact, Aids in calming cats during travel.