You need to get Hulda Clark 's book and read it. You can download it for free.
If you don't get your herbs from the right sources they will not be potent. The Black-Walnut hull tincture at self health resource center is like 3 times stronger than the stuff you buy at health foods stores.
The best way to kill them is to use the herbs AND the zapper at the same time.
You can get a zapper on ebay for about $15-50, or you can make one.
That is, if you BELIEVE you have parasites. But, of course, there's no way to tell if you do or not...