If you were unfortunate enough to be suffering from hemorrhoids, would you consider applying 350 volt electric shocks to the affected area – supplied via an electric fish? Improbable though it may seem, such practices were well known in Roman times – predating modern TENS machines by some 2000 years.
“Ecclesiastes 1:9 states that there is ‘nothing new under the sun’; and such is the case with electrical stimulation. Aristotle, Pliny, and Plutarch recognized the numbing effect of electricity when referring to the application of the torpedo fish to the body. Scribonius Largus advocated the use of piscine electrotherapy for the relief of pain associated with gout, headache, arthritis, and hemorrhoids. Various means of providing electrical current were developed, including the use of the electric ray or great Nile catfish.“ [our hyperlink]
See: ‘The use of transcutaneous neural stimulation and isokinetic testing in arthroscopic knee surgery’, The American Journal of Sports Medicine, Volume: 13, issue: 1, page(s): 27-33.
Also see [electrically related]: The history of voltaic piles.
Coming soon: The medical applications of electric cattle fences.
The photo of Malapterurus electricus is courtesy Stan Shebs @ Wikpedia.