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 structures that grow hair in the scalp. Sebaceous glands produce sebum, which moisturizes hair and skin. Each hair penetrates up through the skin surface along with sebum.

Acne may begin during puberty, and it affects about 80% of all adolescents. It occurs when sebaceous glands in the skin are over-stimulated to produce sebum. Skin cells are not being shed normally, and these sticky cells block the skin's hair follicles, trapping the sebum. The blocked, oil-filled follicle then causes the bacteria normally in the hair follicles to multiply. This leads to inflammation, redness and pimples (pustules).

In adolescents, acne flare-ups probably are related to a natural increase in androgen hormones during the teen years that stimulate the sebaceous glands to produce excess sebum. 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). These 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.

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

Acne cannot be prevented. It's helpful to remember that acne develops in most people and is a normal part of maturing. 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, Sotret, Amnesteem). However, these medications can have side effects and 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 five months of isotretinoin treatment or for one month after treatment.

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.

Acne can result in scarring that your child may regret in later life. Offer treatment and make sure that he or she is aware of the potential for scarring, but remember that if your child does not want treatment, he or she will likely not be compliant with the medications prescribed. 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 work within four to eight weeks. Tretinoin may show peak results in three to six months.

National Institute of Arthritis and Musculoskeletal and Skin Diseases
Information Clearinghouse
National Insitutes of Health
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Bethesda, MD 20892-3675
Phone: 301-495-4484
Toll-Free: 1-877-226-4267
Fax: 301-718-6366
TTY: 301-565-2966
Email: niamsinfo@mail.nih.gov
http://www.niams.nih.gov/