This powerful extract is derived from the hulls of green black walnuts, and has been used for centuries as an herbal tonic to promote healthy microbial activity. Parasites and other unwelcome organisms would be much happier if you did not take Green Black Walnut extract. As an herbal dietary supplement, take 1 2 2 droppersful 2 3 times daily in juice or water, before meals and or at bedtime. This product is best used by gradually increasing dosage over a two week period with a one week break before repeating.