Cats are attracted to catnip because of an oil called nepetalactone. Found in the seeds, leaves and stems of the plant, the oil gives felines a blissful, happy feeling.
Not all cats are attracted to catnip. It is an inherited genetic trait that affects about 50 percent of cats. Very young kittens also are not affected by catnip. For cats who are sensitive to it, the tendency starts to show between 3 and 6 months of age.
Scientists are not certain exactly how catnip creates that blissful feeling. Although some cats eat catnip, really it is the scent of the oil that they are responding to. The most reputable theory is that catnip mimics feline pheromones that trigger happiness.
Catnip affects individual cats in different ways. The most common reaction is extreme calm and mellowness. The cat will often roll around and rub its face on the floor or furniture. Some cats, however, become very excited and playful.
Catnip is non-toxic and does not cause the cat to become addicted to it, so it is a safe treat for cats who enjoy it. It can also be used to train sensitive cats by rubbing it on scratching posts or beds.