You can do what I'm in the middle of...both the Humaworm cleanse to kill parasites, and the Humacleanse (bowel cleaner) to keep things moving and to help push out the dead parasites. I'm almost finished with the month long cleanses, have had absolutly no negative effects. The only thing I notice is that my allergies are lessening...which is great, because Santa Ana season is coming up, and those winds always trigger my allergies...