Isn't this why they make probiotics for dogs? To help replenish the flora and fauna lost in situations like these? I'm not being condescending-I'm seriously asking!?Commercial dewormers, if overused, can be quite harmful to your dog because they clean everything out of their digestive system, including the good stuff. There have been studies recently that show that you can't truly rebuild the good digestive flora and fauna and it is very important for the immune system overall. .