The background: For the last year and a half, I've been deworming my chickens with wazine and safeguard paste (fenbendazole). I dewormed them about 2-3 months ago with Safeguard, but then a few weeks ago, after feeding the flock pumpkin seeds, I found a poop with signs of a tapeworm (tiny little white rice-like things in it). On top of that, some of the chickens were thin. After reading BYC de-worming posts, I discovered Valbazen was the treatment to use for killing tapeworms and dewormed the flock yesterday. After re-reading the BYC posts, it looks like I may have given them a bigger dose than recommended. I gave the standard size chickens 1 cc/ml and the bantams 1/2 cc/ml. I have checked several poops today and most were clean, but I did find 1 poop with 2 dead roundworms in it (about 1.5" long). 20 out of my 21 chickens look good today and are acting normally, but 1 of my hens is acting poorly and since she was fine yesterday, I'm wondering if she is suffering ill effects from the dewormer. The problem: The sick hen is a 2 yr. old Barred Rock. She was totally fine yesterday and I remember her being quite eager to try and steal bread from the other hens yesterday (she wasn't successful). Today, she is acting lethargic and not eating much. When I let the flock out to free-range today, she went off by herself and after drinking out of the dogs' water dish (a daily habit), she stood with her eyes closed and never joined the rest of the flock. An hour later, when I carried her out to the yard, she did eat some dirt and peck at the grass a tiny bit. At dusk, she was able to fly up to her roost to sleep, but I brought her inside to spend the night. Her crop is not full and a bit soft. Twice, I have seen her poop out a tiny bit of white liquid - no real poop in her cage yet and she's been inside for a few hours. I gave her a few droppers full of yogurt with some vitamin B supplement. She currently has access to her feed, grit, and water with apple cider vinegar in it and she will be kept inside tonight, so that she doesn't have to use her energy to keep warm. Tomorrow, I will give her some more yogurt and offer her some scrambled eggs, but she probably won't eat till morning (she's sleeping now). 1. I've read that when deworming for the first time, to use wazine first so that the expulsion of too many worms does not harm the chicken. This was not the first time she was dewormed - in fact, she had just been dewormed 2-3 months ago. Could she have impacted intestines because the valbazen is flushing too many worms out of her system? If so, what can I do for her? 2. Could she be having trouble because I gave her too high of a dose of the dewormer? All 20 pullets/hens of the rest of the flock are fine and the other 15 standards all received the same dose as she did (1 cc/ml).