Is catnip bad for dogs?

For some reason, Dory is eating the catnip that I put down for the cats. I have two thoughts on this, either she genuinely likes the catnip, or she's just eating it to make them mad. The reason I think it might be the second is because she hides their catnip toys in her bed so they can't play with them. She can be a bit bossy with the cats sometimes.:rolleyes:

Is the catnip bad for her?

Any thoughts on why she's doing this?