We have an animal health store here a vet works there so he will give you the pills for worms. When we got Ebony we went ahead and wormed her just to be safe. The vet said the pills wouldn't hurt her if she didn't have worms. Anyway, I think what a vet gives is totally different than the over the counter stuff. If it were me I think I would wait to give them what the vet does. Hope all this made sense.