I used this for the full amount of time. I have three cats, one with a mild aggression problem and one that likes to chew. This product made no difference in their behavior. I placed it in an area that they traffic a lot, and the room is not super-big, so I'm sure the "smell" would have reached them. One of the cats (the aggressive one) did seem to react when he got close to the diffuser by wrinkling his nose up, but that was it.I would definitely not buy this again, especially for the outrageous price.