While they aren’t prone to infection, blackheads can become infected if you pick at them. Symptoms may include swelling, pain, and pus.
Blackheads are a type of noninflammatory acne, meaning they develop closer to your skin’s surface and don’t have a bacterial cause. They happen when a mixture of dead skin cells and oil (sebum) gets trapped in your pores.
Picking at a blackhead can break down the wall surrounding the affected pore, allowing bacteria to enter and rarely causing an infection.
When they aren’t infected, a blackhead looks like a small bump with a dark center.
If it becomes infected, you might also notice:
- redness
- swelling
- white- or yellow-colored pus
In some cases, the affected area grows larger. It may also become painful to the touch. The infection could spread to nearby pores, causing a widespread acne breakout.

You have sebaceous glands, which secrete oil, under each pore. If you have oily skin, these glands may be more active. When the oil combines with dead skin cells on the surface of your skin, it can become trapped in your pores, causing blackheads.
If you pick at a blackhead or try to pop it, you can expose the affected pore to bacteria from your hands or the surrounding skin, causing an infection.
Infected acne doesn’t always require a doctor’s visit. But if you have stubborn pus and redness or other color changes that seem to be spreading, you may need a prescription antibiotic. This may be oral or topical, depending on the severity of the infection. Antibiotics help kill the bacteria that’s causing the infection, as well as decrease overall inflammation.
If you tend to get frequent inflamed and painful breakouts, a doctor might also recommend retinoids. Made from vitamin A-derived ingredients, retinoids help reduce inflammation and prevent debris from collecting in your pores. If you decide to try retinoids, make sure to stock up on sunscreen, as they can make your skin more sensitive to sunlight.
If you have an infected blackhead that’s turned into a large, deep, painful cyst, you may need to have it drained by a dermatologist (a doctor who specializes in skin and hair illness). This can be done with a quick in-office procedure. Alternatively, you can also ask your doctor about a corticosteroid shot. This can help reduce redness and swelling within a few days.
It’s hard to avoid blackheads altogether, but there are several things you can do to prevent them from becoming infected.
First, resist the urge to squeeze or pop blackheads, which can introduce infection-causing bacteria into your pore. Squeezing a blackhead can also just push its contents deeper into your pore, making it larger. It may also leave you with a lingering scar.
Instead, try applying a product containing salicylic acid to the area. This ingredient, which you can find in a range of skin care products online, helps to dry out the contents of blackheads. Just make sure you don’t overdo it. Too much dryness can make your sebaceous glands go into overdrive, causing them to produce more oil.
Blackheads are usually a minor inconvenience, but they can become infected and painful if you pick or squeeze them.
If you have an infected blackhead, try to leave the area alone so it can heal. If it remains painful and swollen after several days, it may be time to see a dermatologist for an antibiotic or a quick procedure to drain the affected area.
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