I also use herbal. I use Fir Meadow herbs; GI Soother for coccidia and barber pole, and DWorm A for stomach and tape worms. I combine both and give it twice weekly at Kat's suggestion, since my area is prime for parasites. It usually keeps them in very nice condition. This year I had one kid come down with cocci -- I treated with acute dosages of Fir Meadow and he cleared amazingly fast. Doing great now. I prefer the herbs as the parasites cannot grow resistant to them, and since I am using the meat and milk from my goats I am more comfortable with that. I love the thought that the herbs nourish their system, instead of stripping the flora like chemicals do.
I don't have anything against chemicals at all, though! I just like using herbs when I can, because then if I NEED a chemical, it has a better chance of working because the parasites on my farm shouldn't have grown resistant.