Comedones are obstructed openings of the sebaceous glands where accumulated sebum becomes discolored upon exposure to air (oxidized). They appear as black dots on the skin, most commonly on the face. Comedones are also referred to as large/coarse pores or "blackheads". When squeezed, the sebum is expelled and can resemble a small worm. While comedones are most commonly associated with acne, they can also occur in other skin conditions.
Comedones form when there is a plug in the opening of the sebaceous gland. This occurs due to increased cell proliferation and a lack of shedding/exfoliation of the uppermost skin cells. In many cases, there is also increased sebum production within the sebaceous gland itself. There are several causes for this to happen, including increased/changed hormone production during puberty. There is also a genetic and ethnic component to comedone formation.
Acne often begins with comedones in early puberty. Many people do not recognize comedones as a form of acne and therefore go untreated for a long time. Acne conditions characterized by comedones are often referred to as comedonal acne. In such cases, it is important to address comedone formation.
Comedones can also be seen in other skin conditions, including hidradenitis suppurativa (chronic inflammation of sweat glands), atheromas (sebaceous cysts), and chronic skin changes related to long-term sun exposure (solar comedones).
It can be tempting to squeeze comedones to remove the sebum. However, one should be cautious with squeezing blackheads, as it can lead to skin infections and/or scarring.
If a person has many comedones, as seen in comedonal acne, treatment should include comedolytic ingredients. Such treatment aims to reduce sebum production and the risk of sebaceous gland blockage. There are various treatment options available, including topical treatments with active ingredients such as retinoids, azelaic acid, and benzoyl peroxide. Oral medication may be considered in cases of severe comedonal acne. Since hormones often playa contributing role, certain contraceptives for women (including combination pills) can also help reduce comedone formation.
It is also important to avoid oily facial products. Oily creams can exacerbate skin blockage, leading to increased comedone formation and acne. If you have comedones, you should use moisturizers and sunscreens specifically formulated for acne-prone skin.
The role of dietary changes in reducing comedonal acne is still debated. Some research articles have suggested a possible correlation between high consumption of dairy products and/or diets high in sugar and fat.
For solar comedones, it is advisable to reduce sun exposure, use sunscreen suitable for acne-prone skin, avoid oily creams, and refrain from smoking.
