Yes that may be right and Charlie has been high as a kite LOL............it wont harm him
I learnt a lesson with Misa, who is such a gentle boy cos I had a tub of nip that they used to sit in and much and roll about and I was collecting seeds last year so my hands spelt of it. I though Misa would like to sniff and lick my hands but he treated them like he would a catnip plant and got quite aggressive,
Thats why you dont take a catnip toy away until they have well and truely finished