Nepetalactone induces a harmless physiological reactions in some cats. This reaction has been studied extensively, and has been found to induce a psychosexual response in both male and female cats. One might say that catnip has an aphrodisiac effect. Cats will try to hide their stash of cat toys. They will also try everything short of hang-gliding to get to their stash of catnip.
Cats usually get very active when sniffling' nip.
This is normal. If however, you find her attacking you,or getting very aggressive, it would be advisable not to give your cat catnip. Not likely, cats seem to know when to say enough. If you give your cat catnip often she will eventually turn her nose away from it's lure. This reaction will not last long though, in a few days she will most likely be Kookin' it up with the ol' stash of Kooky Kat Catnip, and be as kooky as ever.