The history of bullying of electro-therapy by the medical profession is long, going back to the 1750's.
There were zappers back in the 1870's up to 1935, when they suddenly disappeared. They were carried by Montgomery Wards, Sears and Roebuck, and Rexall Drugs, among others.
There is not lack of proof that efficacy is possible as just about anyone can get a microscope and watch the microbes explode under the electrical pulses but the same thing DOES NOT Happen to human blood cells, epithelial cells, etc.
With over 1 million zappers having been sold, and the drug industry looking for any opportunity to defame these products for any possible injury, there has never been any case of significant injury from zapping reported.
There was one very infamous case of a pacemaker failure from zapping, but this was determined to be a known fault of the pacemaker.
I have been using zappers for over 16 years and before you could take my zapper away from me, you would have to take my other favorites that pack a lot of bang.
I trust my zapper far more than I trust vaccinations. My zapper has stopped things that the strongest Antibiotics did not stop. My personal experience.
So doubt if you wish, that is your loss. My personal victory is not in selling zappers, it is in owning the best and the confidence that it brings that I have a better chance of survival than 99 percent of the people here when the next big one comes.