Valbazen and Safeguard are the two most recommended. They recommend using them alternately, so as not to build a resistance to the wormer also.
Better ask someone else for the dosage on the valbazen, as I just ODed mine on the safeguard, not on purpose, just not good with numbers and misread the numbers, so I am definitely not the one to ask about dosage.
So far, mine have not keeled over and are eating, drinking, and acting normal and it's been hours. I used safeguard liquid for goats 10% from
TSC. I'm not sure where to get the valbazen, but have heard it is the better one to use and treats all worms. Safeguard does not treat tapeworm but all others. Do not use wazine, as it only treats roundworms and has become not as effective.
That is the extent of my knowledge...hope someone else, maybe Dawg? will pop in and help? He really knows his stuff when it comes to wormers and chickens in general! Kathy is another one who has a ton of info that is great, but she might be kinda busy? But she also knows her stuff!
There are some threads on here too, that go into everything worms and wormers...I stumbled across one the other night and it had awesome info on it. I just can't find it again or I would put up the link to it. I have been looking for it too!