Catnip, also known as Nepeta cataria, is an herb from the mint family that is known to have a strong effect on cats. It is often used as a recreational drug for cats, and can cause them to become more active and playful. CATMINT, which is also known as Nepeta mussinii, is a similar plant that has a milder effect on cats. It is often used in gardens as an ornamental plant, and is known to attract cats.