Good Morning! Do your parasite cleanse first, then later on if you still feel it's necessary, do the colon cleansing. I don't know about all formulas, but our parasite cleanser has 10 paraite killing herbs, 7 purifying herbs and digestion/colon cleansers all together in each daily dose. The colon cleansers just help your digestive system deal with removing the parasites and their toxins without becoming sluggish, but without diarrea. If you are unsure of how you'll feel, then start your cleanser on the weekend so you'll know how your body will react. Good Luck!