This is an over the counter product - it does not require prescription.
Greenies satisfy your dog's natural desire to chew. The consistency/ingredients have been shown to help reduce odors, control dental tartar (calculus), strengthen gums and diminish oral bacteria.
Some chew products contain other inert materials which are not digestible. All ingredients in Greenies the original smart-treat are highly digestible and, except for the palatability enhancer, are used in human food products.
Greenies prevent buildup of dental calculus, are exceptionally palatable, highly digestible and improve digestibility of other foods.