I agree with the other post about how parasite infections CAN create allergies and maek them worse! It depends on WHAT you are allergic to that determines how herbs will affect you. For example, our formula contains cramp bark; cramp bark contains salicin which is the same componant that is in asprin SO if you're allergic to asprin, then you'll be allergic to cramp bark. Your best bet would be to find the EXACT ingrediants in whatever cleanse you want to try and research them for allergic reactions. I personally think you're better off doing a cleanse than not doing one. I'll be happy to help if I can.