I saved the following from another post by Monroe. I think it is excellent.
CASTOR OIL
Castor oil, when encapsulated and frozen, will pass through the stomach and small intestine before dissolving. Freezing the capsule before ingesting totally eliminates the traditional cramping associated with castor oil liquid because the capsules dissolve in the ileum, the last three fifths of the small intestine. Here the digestive tract hydrolyses this oil into recinoleic acid which whilst harmless to humans is deadly to parasites. The ileum connects to the cecum by way of the ileocecal valve and the majority of parasites of all kinds will nest in the cecum area ( the lower end of the ascending colon where the large bowel begins ). This area is warm and moist, providing a plentiful source of fresh food for these poisonous invaders.
Castor oil not only suffocates parasites but is nature’s penetrating oil for colon plaque. When the castor oil capsule is frozen it does not act as a laxative, is odorless and will not “burp” back. Suggested dosage is 2-6 capsules every 12 hours.

http://health-truth.com/our-program/parasites/parasites-the-merchants-of-mayhem-part-3/

Cod liver oil works the same way except it is easier to freeze, sometimes less expensive but it is not known to be deadly to parasites because of its chemistry. It works because it suffocates them. You can also use frozen pumpkin seed oil, which is another known anti-parasitic.
If you do the frozen cod liver oil I suggest that you take it first thing in the morning on an empty stomach. You can start with 6 capsules and work up to about 12. Worked every time for me. You may find parasites that you have never seen before. This was a game changer for me.