What causes ingrown hairs?

A shaved, waxed, or tweezed hair may have a sharp or altered tip. If it curls toward the skin instead of rising through the follicle opening, the body can react with a small red, itchy, or tender bump. Coarse or tightly curled hair, close shaving, friction, and blocked follicle openings can make this more likely. Ingrown hairs can occur on the face, neck, underarms, legs, bikini area, or anywhere hair is removed.

Several bumps with pus or spreading redness may reflect folliculitis rather than a single trapped hair. Repeated bumps in the beard area can fit pseudofolliculitis barbae, also called razor bumps. Rough follicular bumps on the upper arms or thighs may instead be keratosis pilaris.

Pause shaving, waxing, or tweezing over the irritated area until it settles. Use a warm, clean compress and wash gently; do not dig into the bump, squeeze it, or pull at a buried hair with unclean tools. When you resume shaving, soften the hair first, use shaving gel, follow the direction of growth, and avoid stretching the skin or shaving extremely close. Loose clothing can reduce rubbing in body-fold areas.

If hair removal repeatedly triggers painful bumps, a clinician can discuss options such as changing technique or laser hair removal. Treatment choice depends on skin tone, hair characteristics, body area, and the pattern of irritation.

Arrange a dermatology assessment if bumps keep returning, leave dark marks or scars, form deep painful lumps, or do not improve after stopping hair removal. Seek prompt care for rapidly spreading redness, increasing warmth, severe pain, fever, or feeling unwell, because these features can signal a skin infection needing treatment.

Ask whether the bumps are ingrown hairs, folliculitis, or razor bumps; which hair-removal method is least irritating for your skin; and whether a prescribed cream or another treatment could prevent scarring.