Although several researchers were apparently experimenting with electrical epilation after the Civil War, it's generally accepted that St. Louis ophthalmologist Charles Michel was the first to discover and publish permanent hair removal results with an electrified needle. [7]

In 1875, Dr. Michel reported he had been successfully using a battery-powered needle epilator to treat ingrown eyelashes (trichiasis) since 1869. [8] This DC powered method was called electrolysis because a chemical reaction in the hair follicle causes sodium hydroxide to form, which damages the follicle. It's also sometimes called galvanic electrolysis.

Use of electrolysis for hair removal continued through the early part of the 20th century. Its commercial popularity as a cosmetic treatment was briefly eclipsed by x-ray hair removal, which was advertised as both “painless” and “harmless” (only one of which was true, of course).

Subsequent innovations in the field included the use of multiple needles, developed by Paul Kree in 1916, and the use of AC electricity, which causes thermal damage within the follicle. [9] This was first reported in medical literature in 1924 by Dr. Henri Bordier, following over a decade of experimentation by numerous researchers. [10] This method was called diathermy by Bordier and is also called thermolysis, short-wave, high-frequency (HF), radio-frequency (RF), etc.

Incremental improvements in the equipment and technique continued through World War II. At that time, Arthur Hinkel and Henri St. Pierre applied for a patent for a blend method they'd been developing. They received their patent in 1948, and 20 years later published the groundbreaking book Electrolysis, Thermolysis and the Blend, discussing their use of scientific techniques to improve the method. [11] In the wake of Hinkel's book, several other useful practical overviews have been written. [4, 5, 6]

The second half of the 20th century saw more incremental equipment improvements incorporating transistors and computerized controls, as well as insulated probes and sterile disposable probes.

Despite improvements in equipment, electrolysis remains highly dependent on the skill of the practitioner. Electrolysis trade groups have set standards for member certification, but many U.S. states do not regulate the practice of electrolysis. [12] For this reason, it's very important for consumers to go to a practitioner recommended by someone who is done and happy with the results.