Ingrown hairs occur when your hair, instead of exiting the follicle normally as it grows, imbeds itself in the follicular wall. It occurs more commonly with tightly curled, kinky hair since its tip is likely to pierce the follicular wall as it exists with a screwing motion. As it grows into the surrounding skin, it produces inflammation, which is perceived as swelling redness and pain. Since the most common cause of ingrown hairs is cutting or removal of the hair below the level of the follicular orifice (commonly called a pore by patients), it typically tends to occur on your face, neck, armpits, groin, and legs. The usual sign of this condition are multiple red to flesh-colored bumps, which can be tender or itchy and can become pustular. Sometimes it is possible to see the imbedded coiled hair on magnification.
Medically reviewed by Norman Levine, MD; American Board of Dermatology
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