They should not be used on the eyelashes, inside the nose or ears, on the nipples or genital areas, or on irritated, chapped, sunburned, or cut skin. A small area should be tested for sensitivity or allergic reaction before treating the entire area. Some hair removal experts recommend professional waxing for the best results. An electric current travels down the wire and destroys the hair root at the bottom of the follicle. The loosened hair is then removed with tweezers.
Every hair is treated individually.
Needle epilators are used in electrolysis. Because this technique destroys the hair follicle, it is considered a permanent hair removal method. The hair root may persist, however, if the needle misses the mark or if insufficient electricity is delivered to destroy it. For instance, you can't control hormonal changes that cause new growth. Most people would probably define permanent as 'never comes back,' but from a medical standpoint that may not be practical.