HUMAWORM usually takes 30 days. Other cleanses take different amounts of time according to how they work in the body and the strength of the doses. The younger and weaker parasites tend to go first, while the older ones will take longer to leave.
ALL herbs used for medicinal purposes are like any other drug - an X amount of herb contains an X amount of chemical that will kill an X amount of parasites. Some people are totally cleaned out with one round while others may take 2-3 rounds to get clean. It depends on the health of the person, the type of parasites they are hosting and how many parasites are in their body.
Cleansing should be spaced out 2-3 times per year to avoid creating super parasites that will become resistant to treatments. This is the same thing when anti-biotics are overused and super bugs are created that no anti-biotic can kill.