I haven't purchased a zapper yet and for me, it's like a last line defense if all else fails. It's just too much money and the results don't seem to catch my mind. I'm currently taking some prescription stuff.
From what I've heard, you can easily find if you truly have parasites
by purchasing PinX by Reese at Walgreens. If you get any adverse reactions, it is likely that parasites
There's also something called IVM, usually for horses although it works quite well for our species in determining parasitic load. You typically mix this stuff (per weight) in yogurt. If you feel good for a few hours, it means that you have parasites. It causes them to stop feeding thus the better feeling.
PM me for more info. Have you seen any parasites
in stool? What kind of supplements are you currently taking. What are your symptoms relating to parasites. It might just be a candida infection.