(Acne Vulgaris)

Reviewed/Revised Feb 2023
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What is acne?

Acne is a common skin problem in which pimples appear on your face, chest, shoulders, or back. Pimples are caused by a buildup of dead skin cells and bacteria.

  • Acne happens when dead skin, bacteria, and dried skin oil build up and block a hair follicle (a tiny pocket in your skin where a hair grows)

  • Doctors treat acne with creams and sometimes medicine you take by mouth

  • Severe acne can cause emotional stress—good medical care and seeing a counselor can help

What causes acne?

Acne is caused by skin oils and dead skin cells clogging your hair follicles. The hair follicles can swell and create bumps (blackheads). If certain kinds of bacteria get in the clogged hair follicles, they cause inflammation. The inflammation produces pimples (whiteheads) that may contain pus.

You're most likely to have acne if you're:

Acne due to puberty usually gets better by the time you're in your mid-20s, but some people, especially women, may have acne into their 40s.

Other causes of acne:

  • Hormonal changes in your body because of pregnancy or your periods

  • Using makeup or skin creams that clog pores

  • Taking certain medicines, especially corticosteroids or anabolic steroids

  • Wearing tight clothing that traps sweat

Acne is not caused by any type of sexual activity or not washing your face enough. Doctors don't think your diet has much to do with acne. However, milk products and very sugary foods may have a slight effect.

What are the symptoms of acne?

Look for several types of bumps on your skin such as:

  • Blackheads

  • Whiteheads

  • Pimples

  • Deeper, firm bumps containing pus (nodules)

  • Large, red, painful bumps filled with pus (cysts or abscesses)

How can doctors tell if I have acne?

Doctors can tell you have acne by looking at your skin.

How do doctors treat acne?

Your doctor may have you visit a dermatologist (skin doctor) for treatment. For all acne, doctors will have you:

  • Wash your skin gently with a mild soap 1 or 2 times a day

  • Avoid using greasy makeup

  • Avoid squeezing or tearing your skin because it could cause scarring

The doctor may also:

  • Prescribe a cream to put on your acne

  • Sometimes, prescribe an antibiotic you take by mouth

  • Sometimes, suggest you see a counselor if you're distressed or withdrawn because of your acne

For severe acne, doctors may use other medicine such as:

  • Birth control pills (for women)

  • Corticosteroids, injected into large, swollen cysts or abscesses to help them heal

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