Catnip contains nepetalactone, an essential oil found in the catnip plant. Here's how it affects your cat and why it makes them feel so good.

Catnip can drive kitties of all sizes a little crazy, and its effects have led feline lovers to wonder what makes this little green plant so attractive to them.

Is it possible to give a cat too much catnip? "It's always possible to give too much of anything, so using catnip as directed by each specific product is recommended," advises Dr. Crow.

The herb certainly has a lot of mystery surrounding it, even for the scientists who have tried to dissect its attributes. More: 6 Tips for cat ladies who hate kitty litter 1. What exactly is catnip?