Catnip is actually a perennial herb that belongs to the mint family. There are over 200 different types of catnip out there. There is an oil in the catnip called nepetalactone that causes the effects it does on your cat, although not all cat breeds are of the same size, the smallest amount will work even on Maine Coon cats which can grow to the size of a small dog or even bigger. When you give your cat catnip they will sniff it out and that’s what gives them the high. If they actually eat it then it may put them to sleep.
They say that catnip gives a similar effect and feel to lsd. I’m sure you will notice your cat acting strangely and quite hyper for about 10 minutes or so. Not all cats will have the same reaction to this and you shouldn’t give it to your kittens as they won’t be able to enjoy the experience as they are too young. You don’t have to worry about giving them too much either, it’s not possible for them to overdose on it. Cats are smart enough to know when enough is enough.
I wouldn’t suggest giving it to them everyday but once in a while is great and they love it! It’s fun to see them be playful and having a great time.