Recommended For Cats over the age of seven and for hairball control. Product Information Boost Immune System Health and Help Avoid Hairball Formation Just like Iams Active Maturity , Iams Indoor Hairball Care contains vitamin E to help strengthen your cat's immune system, plus it contains a patent-pending fiber system that helps provide hairball relief. Indoor Hairball Care is also enhanced with vitamin-rich fish oils for overall health. Wholesome protein provides essential amino acids to help maintain healthy muscle tone and promote a shiny skin and coat, and naturally provides taurine for clear eyes and a strong heart.