Closed comedones:
causes, treatment and when to see a doctor in Singapore

What are closed comedones, and how do they differ from blackheads?

A comedone is a blocked hair follicle. Cells lining the follicle are shed too quickly and stick together, oil production is high, and the mix forms a plug. When the opening of the follicle stays closed over that plug, you see a small, firm, skin-coloured or whitish bump with no visible pore: a closed comedone, or whitehead. When the opening widens and the plug is exposed to air, the keratin and melanin at the surface darken, and you see a blackhead, an open comedone. Both come from the same blocked follicle.

Closed comedones are often easier to feel than to see. Running a hand across the forehead or chin picks up a rough, bumpy texture, and side lighting shows a field of tiny raised dots. They are not caused by dirt and are not a hygiene problem, which is why scrubbing does not clear them.

Comedones matter because they are where acne starts. A comedone whose follicle wall inflames or ruptures becomes a papule, a pustule or a nodule, and inflammation is what drives marks and scars. Treating comedones early is how the later stages are kept from starting; the blackheads page covers the open form in detail.

What causes closed comedones?

Closed comedones form when the four drivers of acne line up in a follicle: abnormal shedding of the cells lining it, oil production driven by androgens, the skin bacterium C. acnes, and low-grade inflammation. Some of these you inherit; others you can influence.

• Oil and hormones. Androgen activity raises oil output, which is why comedones often begin in the teenage years and why some adult women notice them along the jaw and chin with hormonal change.
• Products that block follicles. Heavy, occlusive creams, some foundations and sunscreens, hair pomades and oils near the hairline can plug follicles directly. Comedones that cluster along the forehead or where a product is applied are a clue.
• Friction and picking. Squeezing, abrasive scrubs, masks, helmet straps and phones held against the face irritate the follicle and can rupture plugs into inflamed spots.
• Starting a retinoid. In the early phase of a new retinoid, micro-comedones that were already forming can surface faster, a temporary flare known as purging, which settles as the skin adjusts.
• Smoking and diet. Smoking is associated with comedonal acne, and high glycaemic-index foods and dairy may contribute in some people, though diet is rarely the whole story.

Singapore's heat and humidity add sweat and occlusion under make-up, masks and sports gear, so lighter textures and cleansing after exercise help some people. None of this means the skin is dirty, and stripping it with harsh cleansers tends to make congestion worse rather than better.

“A closed comedone is the first lesion of acne. Treating it early is how the inflamed spots and the scars that follow are kept from starting.”

Dr Sin YongOn treating comedones early

Closed comedones or something else? The lookalikes

Several small bumps are mistaken for closed comedones, and each is treated differently. This is a common reason an acne routine fails to work: the bumps were never comedones.

The presence of comedones is a useful clue for a doctor: it separates acne from rosacea, perioral dermatitis and fungal folliculitis at a glance. That is also why a single photograph is rarely enough to diagnose acne, and why the first visit is an examination rather than a product recommendation.

How a doctor treats closed comedones

Closed comedones are treated by normalising the follicle so plugs stop forming, then clearing the plugs already there. The retinoid does the first job; clearing treatments do the second. Done without the retinoid, clearing gives a brief clean spell and then the same congestion.

Lasers and energy devices are directed at the inflammatory part of acne, not at comedones alone, so they are not the first step for a forehead of whiteheads. Where inflamed spots and post-acne marks are part of the picture, they are planned alongside medical treatment on the acne treatment page. A retinoid increases sun sensitivity, so daily sunscreen is part of using it in Singapore, and retinoids are stopped in pregnancy.

When to see a doctor about closed comedones in Singapore

Many people manage a few comedones with a gentle routine and a non-prescription retinoid. It is worth seeing a doctor when:

• comedones persist or spread despite a fair, consistent trial of a retinoid and non-comedogenic products;
• inflamed red spots, pustules or deeper lumps start to appear among them;
• marks, dark patches or pitted scars are being left behind;
• the bumps are itchy, uniform or around the eyes, suggesting fungal acne, milia or syringoma instead;
• you are pregnant, planning pregnancy or breastfeeding, which changes which treatments are safe;
• comedones appeared suddenly with other signs of hormonal change, such as irregular periods or new hair growth.

Dr Sin Yong, an aesthetic physician, grades acne at the first visit as comedonal, papulopustular or nodulocystic, rules out lookalikes such as fungal folliculitis, and treats congestion early rather than waiting for it to clear, because comedones are where the later stages begin. Medical treatment comes first. Where acne is severe, unusual or not responding, he refers to dermatology. Enquiries on WhatsApp are answered in English and Chinese.

At home: cleanse gently twice a day, choose lighter non-comedogenic products, introduce a retinoid slowly, use sunscreen every morning and leave the comedones alone. Squeezing a closed comedone usually ruptures the plug sideways into the skin, turning a non-inflamed bump into an inflamed spot that can mark.