well, we told him he had taken one about 5 mins after, he wasent quite sure if we were joking with him or not, so he hung around another 5 mins or so.
so about 10 mins total from taking it, and leaving. not 100% sure if it had taken full effect, but i can only assume it did shortly after.
what a fun lesson that was
however, for some reason no one will take a skittle or a smartie from me? wierd.