Well, Dr. Clark's book " The Cure For All Diseases " tells you exactly what you need to kill most intestinal parasites. This is extracted from this website:

The parasite Cleanse
Getting rid of all parasites would be absolutely impossible using clinical medicines that can kill only one or two parasites each. Such medicines also tend to make you quite ill. Imagine taking 10 such drugs to kill a dozen of your parasites! Good news, perhaps, for the drug makers but not for you.
Yet three herbs can rid you of over 100 types of parasites! And without so much as a headache! Without nausea! Without any interference with any drug that you are already on! Does this sound too fantastic? Just too good to be true? They are natures gift to us. The herbs are:

Black Walnut Hulls (from the Black-Walnut tree)
Wormwood (from the Artemisia shrub)
Common Cloves (from the clove tree)
These three herbs must be used together. Black-Walnut hull and Wormwood kill adults and developmental stages of at least 100 parasites. Cloves kill the eggs. Only if you use them together will you rid yourself of parasites. If you kill only the adults, the tiny stages and eggs will soon grow into new adults. If you kill only the eggs, the million stages already loose in your body will soon grow into adults and make more eggs. They must be used together as a single treatment.

What you need:
Black Walnut Hull Tincture Extra Strength
Wormwood capsules (200-300mg of Wormwood per capsule)
Cloves capsules (500mg per capsule)
Arginine (500mg per capsule)
Ornithine (500mg per capsule)

Flatworms, roundworms, protozoa, even bacteria and viruses arc remarkably easy to kill using a combination of zapping and this herbal program. Thus it is not just for cancer, but a general treatment that can benefit almost every illness.

Read all of it on page //www.curezone.org/clark/parasites.asp

Sergio