Acne -1

What Is It?

Acne is a common skin condition caused by inflammation of the hair follicles and oil-producing (sebaceous) glands of the skin. Hair follicles are the tiny tubes that hold the hair in the scalp.

Acne may begin during puberty, and affects about 80 percent of all adolescents. It occurs when skin cells are not being shed normally, and these sticky cells block the skin’s hair follicles. This traps a body oil called sebum, which is produced by nearby sebaceous glands. The blocked, oil-filled follicle then causes the bacteria normally in the hair follicles to multiply. This leads to inflammation, redness and the formation of pimples (pustules).

In adolescents, acne flare-ups probably are related to a natural increase in androgen hormones during the teen years. Hereditary factors also contribute to the problem. Other factors that can lead to acne include the use of oily cosmetics, humidity, heavy sweating, and problems with the ovaries or adrenal glands. Acne also can be triggered by drugs such as lithium or steroids, both the type that are prescribed by physicians and potentially harmful “body-building” steroids, Acne is not related to diet or poor hygiene. In fact, too much washing can cause an acne flare-up to get worse.


Acne can cause:

  • Blackheads and whiteheads (comedones) — Comedones are enlarged hair follicles filled with sebum. Blackheads are comedones that have opened to the skin’s surface. The color of the sebum makes them appear black. Whiteheads are comedones that are closed on the surface.

  • Pimples (pustules) — Pustules are inflamed hair follicles. The bacteria in the follicle multiply, attracting infection-fighting cells, which release substances that cause irritation and redness. The follicle then ruptures, and spills the contents into the surrounding skin, which causes more inflammation.

  • Nodules and cysts — These are larger infections of the hair follicles that extend deeper into the skin, forming firm, deep bumps and swellings. Like pimples, they are caused by increased sebum production and the growth of bacteria, which cause irritation and redness.

In girls and women, acne often flares up at certain points in the menstrual cycle.


Your doctor usually can diagnosis acne based on a simple physical examination. He or she will look for acne comedones, pustules, nodules and cysts on your face, chest, back, upper arms and shoulders. He or she also will ask questions about your medical history to try to identify contributing factors. You will be asked about your menstrual history, patterns of hair growth, cosmetics, facial cleansers and medications.

Expected Duration

Acne flare-ups may occur at any time after puberty, but are more common during the teen years.


Unfortunately, acne cannot be prevented if it is going to develop. It’s helpful to remember that acne develops in most people and is a normal part of maturing hormonally. However, some people are more prone to developing acne.


Acne can be treated with:

  • Salicylic acid washes — These washes help to empty comedones of sebum.

  • Benzoyl peroxide gels — These medications are applied to the skin as a thin film. They dry and peel the skin, fight the growth of bacteria, and help to clear blocked hair follicles. Some are available in weaker over-the-counter lotions. If these don’t work, your doctor can prescribe the stronger and more effective gel forms.

  • Tretinoin (Retin-A) — This is applied to the skin as a cream, gel or liquid. It helps to clear the skin of plugged follicles by increasing the turnover of skin cells. Because it also increases the skin’s sensitivity to sunlight, tretinoin should be used with a sunscreen.

  • Antibiotics — Clindamycin (Cleocin) and erythromycin (several brand names) can be applied directly to the skin to reduce the growth of acne-causing bacteria.

If these topical treatments fail, acne is treated next with oral antibiotics (usually tetracyclines) or isotretinoin (Accutane). However, these medications can have side effects and therefore are available only by prescription. Also, because isotretinoin causes birth defects, women on the medication who are sexually active must use contraception to make absolutely sure they do not become pregnant either during the four months of Accutane treatment or for one month after treatment.

When To Call A Professional

Call your doctor if you or your child has acne that is not controlled with over-the-counter washes or gels. Remember that in teenagers, the amount of acne may not be a true gauge of the impact of the problem on a child’s life. Even small amounts of acne can be embarrassing and psychologically painful to young people.

On the other hand, if you perceive your child’s acne as a problem and he or she does not, be patient. You cannot force him or her to want treatment. As friends mature and there are changes in attitude about acne and acne treatment, your child likely will approach you about seeing a doctor.


Acne almost always can be controlled with medication, although results may not be seen for weeks or months. For example, most medicines that are applied to the skin (topical) work within four to eight weeks. Tretinoin may show peak results in three to six months.


Johns Hopkins patient information

Last revised:

Diseases and Conditions Center

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.