Yeah, even some that seemed to be in perfect health, strong, vigorous, growing and eating well, passed worms during treatment. If they are carrying a heavy load, pieces of tapeworms sometimes, or wads of nematodes come out. The will have "the squirts" for 3-5 days. It's pretty nasty but worth it.

Treatment is rough on them so they need to be in fairly good health. There is a right time and a wrong time to do it. It does dehydrate them and it is stressful. But those that can handle it are much better off afterward. They bounce back quickly and start putting on weight.