the main three herbs that kill many different parasites are, blackwalnut hull, Wormwood and clove. Most health food stores carry these products alone or in a combo-pills and tincture.
you can also buy them off the internet if you need to. These products are always by colon items in the stores.
I have under active thyroid and my husband has high blood pressure, we have been taking the herbs with no problems. It may effect others differently, just pay attention to what your body tells you. If you have a problem with any of these then there are other things to try. Some people have an allergic reaction to one or more of these herbs.
Usually the directions have you starting out at a low dose, this gives your body a chance to get use to them...heyjude
the web site, www.innvista.com has some good information, I got lots of my information off there plus other herbs to try for certain parasites, check it out.