A clogged pore is a hair follicle that has become blocked by a mix of dead skin cells, oil, and a structural protein called keratin. These plugs sit inside the tiny openings on your skin’s surface and create small bumps that make your skin feel rough or uneven. In dermatology, clogged pores are called comedones, and they’re the earliest form of acne.
What Happens Inside a Clogged Pore
Your skin constantly sheds dead cells and produces oil through sebaceous glands attached to each hair follicle. Normally, that oil flows up through the pore and spreads across your skin’s surface, keeping it moisturized. A clogged pore forms when dead skin cells stick together instead of shedding, mixing with oil and keratin to create a solid plug inside the follicle. That plug traps everything behind it, and the pore fills up.
Clogged pores are non-inflammatory, meaning the skin around them isn’t red or swollen. They’re bumps you can feel and sometimes see, but they don’t hurt. The trouble starts when bacteria get involved, which can turn a simple clog into a full-blown pimple (more on that below).
Blackheads vs. Whiteheads
There are two types of clogged pores, and the difference comes down to whether the pore stays closed or opens up at the surface.
- Whiteheads (closed comedones): The pore opening remains sealed. Keratin and oil accumulate underneath, creating a small, flesh-colored or white bump.
- Blackheads (open comedones): The pore opening is exposed to air. The material inside oxidizes and also accumulates melanin granules, turning dark. The black color isn’t dirt. It’s a chemical reaction.
Both types are the same color as surrounding skin at first glance, and both are non-inflammatory. They won’t become red or painful unless bacteria colonize the plugged follicle.
Sebaceous Filaments Are Not Clogged Pores
One of the most common mix-ups is confusing sebaceous filaments with blackheads. Sebaceous filaments are small, flat, light-colored spots (usually gray, light brown, or yellow) that appear mostly on the nose and chin. They’re completely normal. Every pore has them. Unlike blackheads, sebaceous filaments don’t have a plug blocking the pore, so oil still travels freely to your skin’s surface.
If you squeeze a blackhead, a dark, waxy plug pops out. If you squeeze a sebaceous filament, you’ll get a thin, threadlike strand of wax, but it will refill within days because it’s just part of how your skin functions. Extracting sebaceous filaments repeatedly can irritate your skin without any lasting benefit.
What Causes Pores to Clog
Hormones and Oil Production
Androgens (a group of hormones that includes testosterone) are the primary driver of oil production. They stimulate the sebaceous glands to produce more sebum, and this is why clogged pores and acne peak during puberty, menstrual cycles, and other hormonal shifts. Some people don’t even need high androgen levels; their oil glands are simply more sensitive to normal amounts of the hormone. Insulin and insulin-like growth factor also boost sebum output, which is one reason high-sugar diets are sometimes linked to breakouts.
Air Pollution and Smoking
Ozone, cigarette smoke, and UV rays oxidize a natural oil in your sebum called squalene. When squalene oxidizes, it produces molecules that actively promote pore clogging. Polluted air also lowers levels of linoleic acid on the skin’s surface, further shifting the skin’s oil balance in a direction that favors comedone formation. If you live in a city with heavy air pollution, your skin is dealing with this process daily.
Skincare Products
Some ingredients are more likely to clog pores than others. The comedogenic scale rates ingredients from 0 (won’t clog pores) to 5 (highly likely to clog pores). In theory, sticking to ingredients rated 2 or below reduces your risk. Isopropyl palmitate, for example, is a common ingredient in cleansers and moisturizers that scores high on this scale. That said, the scale was developed using rabbit ear tests decades ago, so real-world results on human skin can vary depending on the full product formula and your individual skin.
How Clogged Pores Become Pimples
A clogged pore is a quiet problem until bacteria enter the picture. A specific skin bacterium, commonly known as C. acnes, thrives in the oxygen-poor, oil-rich environment of a plugged follicle. It breaks down the trapped oil into free fatty acids, which are thicker and stickier than the original oil, making the blockage worse. At the same time, the bacterium produces enzymes that damage surrounding tissue and trigger your immune system to respond with inflammation. That’s the redness, swelling, and pain of a pimple.
In people with acne, the bacterial diversity inside follicles drops significantly. One particularly aggressive strain dominates, forming biofilms (a protective coating that makes it harder to treat) faster than other strains and showing increased tolerance to antibiotics. Inflammatory acne lesions have roughly double the concentration of this bacterium compared to healthy skin, where a more balanced mix of microbes keeps things in check.
Who Gets Clogged Pores
Almost everyone. Approximately 85% of people between ages 12 and 25 experience some form of acne, and it nearly always starts with clogged pores. Prevalence estimates in adolescents range from 35% to nearly 100% depending on the population studied. It doesn’t disappear after your teenage years, either: up to 20% of adult women and 8% of adult men continue to deal with acne, often in a pattern dominated by comedones along the jawline and chin.
How to Treat and Prevent Clogged Pores
At-Home Options
Salicylic acid is one of the most effective over-the-counter ingredients for clogged pores. It’s oil-soluble, so it can penetrate into the pore itself rather than just working on the surface. Once inside, it dissolves the protein connections holding dead skin cells together, loosening the plug so it can clear out. Products with 0.5% to 2% salicylic acid used consistently are a good starting point.
Benzoyl peroxide kills acne-causing bacteria and helps prevent clogged pores from turning inflammatory. Topical retinoids (vitamin A derivatives available over the counter as adapalene or by prescription) speed up skin cell turnover so dead cells shed before they can accumulate. The 2024 American Academy of Dermatology guidelines give strong recommendations to both benzoyl peroxide and topical retinoids for acne management. Azelaic acid receives a conditional recommendation as well, and it’s a good alternative for sensitive skin.
Combining products with different mechanisms tends to work better than relying on a single ingredient. For example, using a retinoid at night and benzoyl peroxide in the morning addresses both the dead-cell buildup and the bacterial component.
Professional Treatments
Dermatologists can perform manual extractions using sterile tools to clear stubborn comedones without the scarring risk of squeezing at home. Chemical peels are another option. Superficial peels using glycolic acid, lactic acid, or salicylic acid penetrate the outermost layer of skin, with exfoliation occurring over several days and full skin recovery within 7 to 10 days. These can be repeated at relatively short intervals. Medium-depth peels go further, with full exfoliation taking 10 to 14 days, and are typically used for more persistent concerns.
For hormonal patterns of clogged pores, especially in adult women, options like combined oral contraceptive pills or spironolactone (which reduces androgen activity) can address the root cause of excess oil production rather than just managing what’s happening on the surface.