Definition: Ingrown hairs and razor bumps refer to the same condition. Both fall under the medical term "Pseudofolliculitis" (or PFB).

Hairs normally grow straight out of a tube in the center of a hair follicle. "Straight" hairs have a circular (o) cross-section while "curly" hairs have an oval (0) cross-section, and tend to fold or curve like a tulip's leaf.

An ingrown hair is a hair that does not grow straight out of the follicle opening. Instead, it curls into the side wall of the hair follicle or into the skin surface. This penetration into and through the wall of the hair follicle produces an inflammation, which can result in the development of a pimple (such as a papule or a pustule) or a cyst (nodule). These lesions are usually tender.

As the hair continues to grow above the opening of the follicle, it can pull the hair tip out of, or keep the hair tip from growing into the side of the follicle. Alternatively, the hair tip may continue to grow into the adjacent skin outside of the follicle and may produce a larger and more inflamed area. This inflammation can produce permanent scarring and/or color changes of the skin (such as darkening [hyperpigmentation] and/or lightening [hypopigmentation]).

Animated Explanations:

Ingrown Hair and EpiLight Animation #1

This animation contrasts normal hair growth with an ingrown hair. It shows how an ingrown hair grows into the wall of the hair follicle. In the animation, the ingrown hair is treated with EpiLight which obliterates the hair. After EpiLight treatment, a new hair is sometimes able to grow back, but usually only a much thinner hair that may not become ingrown because it is thinner and less likely to penetrate the follicle wall.

Ingrown Hair and EpiLight Animation #2

This animation is similar to the one above. However, in this case no hair grows back after the EpiLight treatment. As stated above, EpiLight treatment can result in either a thin hair growing back to replace an obliterated one, or no hair regrowth.

Learn about permanent treatment using pulsed light and lasers.

In-depth information on ingrown hairs is available on ingrownhairs.com.

Interested in treatment by Dr. Jay personally? Call our office at 212-755-2237 to setup an appointment.