I have read that they paralyze the worms and inadvertantly kill them . The paralysis this sometimes causes starving as it makes them detach from the intestinal lining and immoblizes them. Eating raw pumpkin seeds or pumpkin seed oil (unrefined) the same time you take your parasite cleanse herbs-- or also during the day when you eat raw pineapple, raw papaya seeds, or raw garlic will only help kill off more parasites daily.
It's like using a stun gun before the kill- ( stun gun? tazer gun?..yeeesh!!!-- listen to me! :P )