The answer depends on how rough your cat plays when the catnip reaction kicks in. Any toy can be picked or chewed apart, and some cats are more determined than others to get to the source of the smell. Basically, a catnip toy can last anywhere from a few days to several years. Keep in mind that pricier toys with durable, double-layered materials will stay intact longer than cheap toys made of flimsy fabric. Additionally, just like catnip in loose form, the catnip effect of catnip toys fades over time, which varies from toy to toy depending on its potency.