I don't know if they work - I bought the world's smallest zapper on e-bay almost 2 years ago for $10 during the worst of the brain fog, and couldn't even get it together to use it, I was so sick. I then put it away after reading that it was not strong enough to reach some internal parasites, but since then I have read some good reports on zapping. I am so electrically sensitive - I don't know. Possibly can't hurt to try ??