Photothermolysis
The treatment is safe and effective.
Intense pulsed light (IPL) is a technology used by cosmetic and medical practitioners to perform various skin treatments for aesthetic and therapeutic purposes, including hair removal, photorejuvenation (e.g. the treatment of skin pigmentation, sun damage, and thread veins) as well as to alleviate dermatologic diseases such as acne.
The IPL technology uses a high-powered, hand-held, computer-controlled flashgun to deliver an intense, visible, broad-spectrum pulse of light, generally in the visible spectral range of 400 to 1200 nm. Various cutoff filters are commonly used to selectively filter out shorter wavelengths, especially potentially damaging ultra violet light. The resulting light has a spectral range that targets specific structures and chromophores (e.g. melanin in hair, or oxyhemoglobin in blood vessels) that are heated to destruction and reabsorbed by the body. IPL shares some similarities with laser treatments, in that they both use light to heat and destroy their targets. But unlike lasers that use a single wavelength (color) of light which typically matches only one chromophore and hence only treats one condition, IPL uses a broad spectrum wavelength.
Hair removal
IPL can reduce hair growth, most effectively in darker, coarser hair. There are many names and devices for pulsed light treatments such as E-Light, ELOS, and M-Light. IPL should not be confused with laser hair removal , a different procedure using coherent, monochromatic laser light.
Protocol
Broad- spectrum light is applied to the surface of the skin , targeting melanin. This light travels through the skin until it strikes the hair shafts or hair follicle . The follicle is usually where the highest concentration of melanin is located. As the light is absorbed, the bulb and most of the hair shaft are heated, destroying the hair-producing papilla . It is also claimed that heat conversion occurs directly in the darker capillaries that bring blood to the follicle.
At any one time, not all hair follicles are 'active', and only active hair follicles can be affected by the treatment. 'Inactive' hair follicles can be treated as they become 'active' over time. For IPL treatments, an average of 8–10 treatments are required to remove most visible hair. No common treatment protocol exists and it depends on the equipment used and patient skin type. The area to be treated should be clean shaven and free of sunburn. Treatment sessions are usually 4 to 6 weeks apart. Treatments are often given in doctors' offices and so-called "medspas" by trained practitioners.
Contrary to what is often claimed, photoepilation is not a permanent hair removal method but a permanent hair reduction method. Although IPL treatments will permanently reduce the total number of body hairs, they will not result in a permanent removal of all hair. This distinction is only relevant in the USA because of FDA wording.
Certain skin conditions, health irregularities, and medications can impact whether it is safe for a person to receive a light-based hair removal treatment. Photo-sensitizing medications, or damage to the skin are contraindications to treatment. According to Remington , manufacturer of an IPL device, all IPL and laser devices should only be used on light to medium skin tones, and work best on darker hair.