We recently adopted a kitten. He is about 8 weeks old. The girl who gave it to us said her vet had wormed it. (Which I do believe!). My question is.....how long does it take for worm meds to take effect? We have noticed a few little rice looking pieces by his tail. (I only noticed this an hour ago. Let me just say.....gag. ) Does this mean that the medicine is working? He has his own litter box, so my other two are not using the same box. I have an appointment this week with the vet, but I am a little freaked out. Any advice from cat owners out there? Thanks!