Causes

Acne occurs when tiny holes on the surface of the skin become clogged. These holes are called pores.

• Each pore opens to a follicle. A follicle contains a hair and an oil gland. The oil released by the gland helps remove old skin cells and keeps your skin soft.
• When glands produce too much oil, the pores can become blocked. Dirt, bacteria, and cells build up. The blockage is called a plug or comedone.
• If the top of the plug is white, it is called a whitehead.
• If the top of the plug is dark, it is called a blackhead.
• If the plug breaks open, swelling and red bumps occur.
• Acne that is deep in your skin can cause hard, painful cysts. This is called cystic acne.

Acne is most common in teenagers, but anyone can get acne, even babies. Three out of four teenagers have some acne. Hormonal changes may cause the skin to be more oily.

Acne tends to run in families. It may be triggered by:

• Hormonal changes related to puberty, menstrual periods, pregnancy, birth control pills, or stress
• Greasy or oily cosmetic and hair products
• Certain drugs (such as steroids, testosterone, estrogen, and phenytoin)
• High levels of humidity and sweating

Research does not show that chocolate, nuts, and greasy foods cause acne. However, diets high in refined sugars may be related to acne.

Symptoms

Acne commonly appears on the face and shoulders, but it may also occur on the trunk, arms, legs, and buttocks.

• Blackheads
• Crusting of skin bumps
• Cysts
• Papules (small red bumps)
• Pustules
• Redness around the skin eruptions
• Scarring of the skin
• Whiteheads

Exams and Tests

Your doctor can diagnose acne by looking at your skin. Testing is usually not needed.

Treatment

SELF-CARE

Steps you can take to help your acne:

• Clean your skin gently with a mild, nondrying soap (such as Dove, Neutrogena, Cetaphil, CeraVe, or Basics). Remove all dirt or make-up. Wash once or twice a day, including after exercising. However, avoid scrubbing or repeated skin washing.
• Shampoo your hair daily, especially if it is oily. Comb or pull your hair back to keep the hair out of your face.

What NOT to do:

• Try not to squeeze, scratch, pick, or rub the pimples. Although it might be tempting to do this, it can lead to skin infections and scarring.
• Avoid wearing tight headbands, baseball caps, and other hats
• Avoid touching your face with your hands or fingers.
• Avoid greasy cosmetics or creams. Take off make-up at night. Look for water-based or "noncomedogenic" formulas. Noncomedogenic products have been tested and proven not to clog pores and cause acne.

If these steps do not clear up the blemishes, try over-the-counter acne medications. You apply these products directly to your skin.

• They may contain benzoyl peroxide, sulfur, resorcinol, or salicylic acid.
• They work by killing bacteria, drying up skin oils, or causing the top layer of your skin to peel.
• They may cause redness or peeling of the skin.

A small amount of sun exposure may improve acne a little, but mostly it just hides the acne. However, too much exposure to sunlight or ultraviolet rays is not recommended because it increases the risk for skin cancer.

PRESCRIPTION MEDICINES

If pimples are still a problem, a health care provider can prescribe stronger medications and discuss other options with you.

Antibiotics may help some people with acne:

• Oral antibiotics (taken by mouth) such as tetracycline, doxycycline, minocycline, erythromycin, trimethoprim, and amoxicillin
• Topical antibiotics (applied to the skin) such as clindamycin, erythromycin, or dapsone

Creams or gels applied to the skin may be prescribed:

• Retinoic acid cream or gel (tretinoin, Retin-A)
• Prescription formulas of benzoyl peroxide, sulfur, resorcinol, or salicylic acid
• Topical azelaic acid

For women whose acne is caused or made worse by hormones:

• A pill called spironolactone may help
• Birth control pills may help in some cases, though they may make acne worse

Minor procedures or treatments may also be helpful:

• A laser procedure called photodynamic therapy
• Your doctor may also suggest chemical skin peeling, removal of scars by dermabrasion, or removal, drainage, or injection of cysts with cortisone

People who have cystic acne and scarring may try a medicine called isotretinoin (Accutane). You will be watched closely when taking this medicine because of its side effects.

Pregnant women should NOT take Accutane, because it causes severe birth defects. Women taking Accutane must use two forms of birth control before starting the drug and enroll in the iPledge program. Your doctor will follow you on this drug and you will have regular blood tests.

Outlook (Prognosis)

Acne usually goes away after the teenage years, but it may last into middle age. The condition often responds well to treatment after 6 - 8 weeks, but it may flare up from time to time.

Scarring may occur if severe acne is not treated. Some people, especially teenagers, can become very depressed if acne is not treated.

When to Contact a Medical Professional

Call your doctor or a dermatologist if:

• Self-care measures and over-the-counter medicine have not helped after several months
• Your acne is severe (for example, you have a lot of redness around the pimples or you have cysts)
• Your acne is getting worse
• You develop scars as your acne clears up

Call your baby's health care provider if your baby has acne that does not clear up on its own within 3 months.

Alternative Names

Acne vulgaris; Cystic acne; Pimples; Zits

References

Acne, rosacea, and related disorders. In: Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, Pa: Saunders Elsevier; 2009:chap 7.

Updated: 4/22/2012

Reviewed by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.