the whole point of getting well is to STOP putting harmful things into your body; bad food, bad air, bad liquid... high voltage electricity is in that 'bad for you' list. 3 years ago I went through a medical procedure where 75 volts of electricity were pumped into me supposedly for therapy (not mental therapy, it was done as physical therapy). little did i know it would completely disable me, lost my $125K job a year, my home, my body, unable to work or play since. my nervous system was completely trashed.
zappers are 9 volts, from what i hear. granted that's not as much as i had, but still... doesn't matter whether a "naturalist" like clarke recommends it or a doctor does. take my word for it, you have no idea what you're truly playing with when you plug that thing in and touch yourself with it.
my attitude is - the more gentle and more in accord with nature - the better, and zappers are not in that group. same goes for the 'new age' ACV machines - they use voltage, and not always alittle.