blackhead

Blackhead, or open comedone, is a non-inflammatory acne lesion that forms when a hair follicle becomes clogged with keratin, sebum, and shed skin cells. The opening of the follicle remains exposed to the air, and the material inside oxidizes, turning dark brown or black, which gives the lesion its characteristic appearance. The black color is due to oxidation, not dirt.

Most commonly it appears on the face—especially the nose, chin, and forehead—but can occur on the chest, shoulders, and back. It is particularly prevalent during adolescence due to hormonal changes, though it can persist into adulthood.

Causes include excess sebum production, hyperkeratinization of the follicular lining, and factors such as cosmetics, friction, and environmental humidity. Oily skin types are more prone.

Diagnosis is clinical. Blackheads are differentiated from whiteheads (closed comedones) and inflammatory acne by their openness and lack of surrounding erythema.

Treatment and management usually involve: regular gentle cleansing; topical keratolytics such as salicylic acid or beta-hydroxy acids; retinoids (adapalene, tretinoin) to normalize follicular keratinization; and, in some cases, benzoyl peroxide to reduce bacteria and inflammation. In persistent or troublesome cases, a dermatologist may perform comedone extraction. Avoid squeezing, picking, or using unsterilized tools to prevent scarring and inflammation.

Prevention focuses on using non-comedogenic skin products, avoiding heavy or oily cosmetics, and incorporating gentle exfoliation as tolerated. Some individuals may benefit from hormonal therapy or isotretinoin in severe, persistent cases. Prognosis is generally favorable with appropriate treatment, though blackheads may recur in acne-prone individuals.