Acne is a disorder
of the skin’s oil glands (sebaceous glands) that results in plugged pores
and outbreaks of lesions commonly called pimples or zits. Acne lesions
usually occur on the face, neck, back, chest, and shoulders. Nearly 17
million people in the United States have acne, making it the most common
skin disease. Although acne is not a serious health threat, severe acne
can lead to disfiguring, permanent scarring, which can be upsetting for
people who suffer from the disorder.
Does Acne Develop?
acne as a disease of the pilosebaceous units. Found over most of the body,
pilosebaceous units consist of a sebaceous (oil) gland connected to a
hair-containing canal called a follicle (see figure
units are largest and most numerous on the face, upper back, and chest—areas
where acne tends to occur. The sebaceous glands make an oily substance
called sebum that normally empties onto the skin surface through the opening
of the follicle.
Acne is believed
to result from a change in the inner lining of the follicle that prevents
the sebum from passing through. For reasons not understood, cells from
the lining of the follicle are shed too fast and clump together. The clumped
cells plug up the follicle’s opening so sebum cannot reach the surface
of the skin. The mixture of oil and cells causes bacteria that normally
live on the skin, called Propionibacterium acnes (P. acnes), to
grow in the plugged follicles. These bacteria produce chemicals and enzymes
that can cause inflammation. (Inflammation is a characteristic reaction
of tissues to disease or injury and is marked by four signs: swelling,
redness, heat, and pain.) When the plugged follicle can no longer hold
its contents, it bursts and spills everything onto the nearby skin—sebum,
shed skin cells, and bacteria. Lesions or pimples develop as a result
of the skin’s being irritated.
People with acne
frequently have a variety of lesions, some of which are shown in figures
2, 3, and 4. The basic acne lesion, called the comedo (kom´-e-do)
or comedone, is simply an enlarged hair follicle plugged with oil and
bacteria. This lesion is often referred to as a microcomedo because it
cannot be seen by the naked eye. If the plugged follicle, or comedo, stays
beneath the skin, it is called a closed comedo or whitehead. Whiteheads
usually appear on the skin surface as small, whitish bumps. A comedo that
reaches the surface of the skin and opens up is called a blackhead because
it looks black on the skin’s surface. This black discoloration is not
due to dirt. Both whiteheads and blackheads may stay in the skin for a
acne lesions can develop, including the following:
lesions that usually appear as small, pink bumps on the skin and can
be tender to the touch.
- Pustules (pimples)—inflamed,
pus-filled lesions that can be red at the base.
painful, solid lesions that are lodged deep within the skin.
inflamed, pus-filled lesions that can cause pain and scarring.
The exact cause of
acne is unknown, but doctors believe it results from several related factors.
One important factor is rising hormone levels. These hormones, called
androgens (male sex hormones), increase in both boys and girls during
puberty and can cause the sebaceous glands to enlarge and make more sebum.
Another factor is heredity or genetics. Researchers believe that the tendency
to develop acne can be inherited from parents. For example, studies have
shown that many school-age boys with acne have a family history of the
Factors That Can
Contribute to Acne or Make It Worse
Several factors can
contribute to the cause of acne or make it worse. Changing hormone levels
in girls and women may cause a flare in their acne 2 to 7 days before
their menstrual period starts. Hormonal changes related to pregnancy or
starting or stopping birth control pills can also cause acne. Stress,
particularly severe or prolonged emotional tension, may aggravate the
In addition, certain
drugs, including androgens, lithium, and barbiturates, are known to cause
acne. Greasy cosmetics may alter the cells of the follicles and make them
stick together. Friction caused by leaning on or rubbing the skin or the
pressure from bike helmets, backpacks, or tight collars can contribute
to or worsen acne. Also, environmental irritants (such as pollution and
high humidity), squeezing or picking at blemishes, and hard scrubbing
of the skin can make acne worse.
Myths About the
Causes of Acne
There are many myths
about what causes acne. Chocolate and greasy foods are often blamed, but
research has shown that foods seem to have little effect on the development
and course of acne in most people. Another common myth is that dirty skin
causes acne; however, blackheads and other acne lesions are not caused
People of all ages
get acne, but it is most common in adolescents. Nearly 85 percent of adolescents
and young adults between the ages of 12 and 24 develop the disorder. People
of all races can have acne, but it is more common among Caucasians. For
most people, acne tends to go away by the time they reach their thirties;
however, some people in their forties and fifties continue to have the
Is Acne Treated?
By the time many
people consult a doctor for their acne, they usually have tried a drawerful
of over-the-counter (OTC) medications. Acne is often treated by a dermatologist,
a doctor who specializes in diseases and disorders of the skin. Dermatologists
treat all kinds of acne, particularly severe cases. Doctors who are general
or family practitioners, pediatricians, or internists may treat patients
with milder cases of acne.
The main goal of
acne treatment is to prevent scarring. Additional goals are to reduce
the number of painful lesions and to minimize the psychological stress
and embarrassment caused by this disease. Doctors often use drug therapy
as the first choice for treating acne. Drug therapy is aimed at reducing
several problems that play a part in causing acne: abnormal clumping of
cells in the follicles, increased oil production, the bacterium P.
acnes, and inflammation. Depending on the severity of the person’s
acne, the doctor will recommend one of several OTC or prescription topical
medications (medication applied to the skin) or a prescription systemic
medication (medication taken by mouth). The doctor may suggest using more
than one topical medication or using both an oral medication and a topical
medication at the same time.
Over-the-Counter Topical Medications Used To Treat Acne
peroxide cream, gel, lotion,
Clearasil, Fostex, PanOxyl Dryox,
Stridex, Oxy Night Watch,
Clearasil Clearstick Maximum Strength
Sulpho-Lac Acne Medication, Liquimat,
Therac Lotion, Sulmasque
Benzoyl peroxide and sulfur
Dryox 10S, Dryox 20S 10, Sulfoxyl
Sulfur and resorcinol
Lotion, Rezamid Lotion,
included in this fact sheet are provided as examples only, and their inclusion
does not mean that these products are endorsed by the National Institutes
of Health or any other Government agency. Also, if a particular brand
name is not mentioned, this does not mean or imply that the product is
for Blackheads, Whiteheads, and Mild Inflammatory Acne
Doctors usually recommend
an OTC or prescription topical medication for people with blackheads,
whiteheads, and mild inflammatory acne. Depending on the type of medication,
a topical drug is applied directly to the acne lesions or to the entire
area of skin affected. The medication helps limit the formation of new
blackheads and whiteheads and decrease inflammation.
for Moderate to Severe Inflammatory Acne
Patients with moderate
to severe inflammatory acne may be treated with an OTC or prescription
topical medication, a prescription oral medication, or a combination of
Topical OTC Medications
resorcinol, salicylic acid, and sulfur are the most common topical OTC
medications used to treat acne. Each works a little differently. Benzoyl
peroxide is best at killing P. acnes and may reduce oil production.
Resorcinol, salicylic acid, and sulfur help break down blackheads and
whiteheads. Salicylic acid also helps cut down the shedding of cells lining
the follicles of the oil glands. Topical OTC medications are available
in many forms, such as gel, lotion, cream, soap, or pad.
In some patients,
OTC acne medications may cause side effects such as skin irritation, burning,
or redness. Some people find that the side effects lessen or go away with
continued use of the medication. Severe or prolonged side effects should
be reported to the doctor.
OTC topical medications
are usually moderately effective in treating acne when used regularly.
Patients must keep in mind that it can take between 4 and 8 weeks before
they notice an improvement in their skin.
Several types of
prescription topical medications are used to treat acne, including benzoyl
peroxide, antibiotics, tretinoin, adapalene, and azelaic acid. Prescription
and OTC benzoyl peroxide work in the same way. Many doctors prescribe
benzoyl peroxide instead of recommending OTC versions to make sure patients
get the most desirable formulation (cream, gel, or lotion).
|Common Prescription Topical Medications Used
To Treat Acne
| • Benzoyl peroxide
|| • Adapalene gel (Differin)
| • Clindamycin phosphate (Cleocin T)
|| • Azelic acid (Azelex)
| • Erythromycin
|| • Benzoyl peroxide and sulfur
| • Tetracycline HCL
|| • Erythromycin and benzoyl peroxide
| • Tretinoin (Retin-A, Avita)
|| • Sulfur and resorcinol
Antibiotics and azelaic
acid help stop or slow the growth of P. acnes and reduce inflammation.
Tretinoin, a type of drug called a retinoid that contains vitamin A, is
the most effective topical medication for stopping the development of
new comedones. It also fights acne by increasing cell turnover, which
helps unplug existing comedones, and thereby allows other topical medications,
such as antibiotics, to penetrate the follicles better. The doctor may
also prescribe a newer drug called adapalene gel, a retinoidlike compound
that helps decrease microcomedone formation.
medications come in a variety of products. The doctor will consider the
patient’s skin type when prescribing a product. Creams and lotions are
moisturizing and tend to be good for people with dry skin. Gels and solutions
are generally alcohol based and tend to dry the skin, so patients with
excessively oily skin or those who live in hot, humid climates may prefer
a gel. The doctor will tell the patient how to apply the medication and
how often to use it.
Some people develop
side effects from using prescription topical medications. Common side
effects include stinging, burning, redness, peeling, scaling, or discoloration
of the skin. With retinoids, these side effects usually decrease or go
away after the medication is used for a period of time. Patients should
report prolonged or severe side effects to their doctor. Between 4 and
8 weeks will most likely pass before patients see improvement in their
For patients with
moderate to severe acne, the doctor often prescribes oral antibiotics
(taken by mouth) in addition to topical medication. Oral antibiotics are
thought to help control acne by curbing the growth of P. acnes
and decreasing inflammation. Common antibiotics used to treat acne are
tetracycline, minocycline, doxycycline, and erythromycin. Some people
have side effects when taking these antibiotics, such as photosensitivity
(higher risk of sunburn), upset stomach, dizziness or lightheadedness,
and skin discoloration. Tetracycline is not given to pregnant women or
children under 12 years of age because it can discolor developing teeth.
Tetracycline and minocycline also decrease the effectiveness of birth
control pills, so a backup or alternative form of birth control must be
used. Patients usually must take oral antibiotics for as long as 4 to
6 months to effectively treat acne.
for Severe Nodular or Cystic Acne
People with severe
nodular or cystic acne should be treated by a dermatologist. For patients
with severe inflammatory acne that does not improve with other medications,
such as those described above, isotretinoin (Accutane), a retinoid, may
be needed. Isotretinoin is an oral drug and is usually taken once or twice
a day for 16 to 20 weeks. It is believed to markedly reduce the size of
the oil glands so that much less oil is produced. As a result, the growth
of P. acnes is decreased. Isotretinoin also reduces cell shedding
and the stickiness of cells in the follicles, which helps prevent the
development of comedones.
Isotretinoin is a
very effective medication that can help prevent extensive scarring in
patients. After 16 to 20 weeks of treatment with isotretinoin, acne completely
or almost completely goes away in most patients (up to 90 percent). For
some people, however, the acne will come back, and they will need additional
treatment with isotretinoin.
Patients should carefully
consider the several disadvantages of isotretinoin. The drug is not only
expensive but is also linked to some adverse effects that can be severe.
Possible side effects include inflammation of the lip and mucous membrane
of the eye; dry mouth, nose, or skin; itching; nosebleeds; muscle aches;
photosensitivity; and, rarely, decreased night vision. Other more serious
side effects include increased blood cholesterol, lipid, and triglyceride
levels and abnormal liver enzymes. To make sure isotretinoin is stopped
if these side effects occur, the doctor usually monitors a patient’s complete
blood count, blood chemistries, cholesterol, triglycerides, and liver
enzymes before therapy is started and periodically during treatment. All
of these side effects usually go away after the medication is stopped.
Patients who experience side effects while using isotretinoin should tell
their doctor. The doctor may be able to reduce the dose of the drug so
that the side effects are decreased or stopped.
The most serious
potential adverse effect of isotretinoin is that it is teratogenic: it
can cause birth defects in the developing fetus of pregnant women who
take the drug. Therefore, it is crucial that women of childbearing
age are not pregnant and do not get pregnant while taking isotretinoin.
Women must use an appropriate birth control method for 1 month before
therapy begins, during the entire course of therapy, and for 1 full month
after therapy stops. Women should talk to their doctor about when it is
safe to get pregnant after therapy with isotretinoin has stopped.
for Hormonally Influenced Acne
For some female patients,
treatment-resistant acne is caused by excessive production of hormones
called androgens. Clues that help the doctor diagnose hormonally influenced
acne are adult-onset acne, hirsutism (excessive growth of hair or hair
in unusual places), premenstrual acne flares, irregular menstrual cycles,
and elevated blood levels of certain androgens.
The doctor may prescribe
one of several drugs to treat women with this type of acne. Low-dose estrogen
birth control pills help suppress the androgen produced by the ovaries.
Low-dose corticosteroid drugs, such as prednisone or dexamethasone, may
have an anti-inflammatory effect and suppress the androgen produced by
the adrenal glands. Finally, the doctor may prescribe an antiandrogen
drug, such as spironolactone, which helps prevent androgens from causing
excessive oil production. Spironolactone also stops androgen production
in the ovaries and adrenal glands. Side effects of antiandrogen drugs
may include menstrual irregularities, breast tenderness, headache, and
Treatments for Acne
Doctors may use other
types of procedures in addition to drug therapy to treat patients with
acne. The doctor may remove the patient’s comedones during office visits.
Sometimes the doctor will inject a corticosteroid drug directly into lesions
to help reduce the size and symptoms of tender and inflamed cysts and
nodules. Other patients may benefit from light skin-peeling agents that
are prescribed by a doctor or applied in the doctor’s office. For some
patients, the doctor may suggest a minor surgical or medical procedure
to help reduce scarring caused by acne.
Should People With Acne Care for Their Skin?
Clean Skin Gently
People with acne
may try to stop outbreaks and oil production by scrubbing their skin and
using strong detergent soaps. However, scrubbing will not improve acne;
in fact, it can make the problem worse. Most doctors recommend that people
with acne gently wash their skin with a mild cleanser, once in the morning
and once in the evening. Patients should ask their doctor or another health
professional for advice on the best type of cleanser to use. The skin
should also be washed after heavy exercise. Patients should wash their
face from under the jaw to the hairline; rough scrubs or pads should not
be used. It is important that patients thoroughly rinse their skin after
washing it. Astringents are not recommended unless the skin is very oily,
and then they should be used only on oily spots. Doctors also recommend
that patients regularly shampoo their hair. Those with oily hair may want
to shampoo it every day.
Handling of the Skin
People who squeeze,
pinch, or pick their blemishes risk developing scars. Acne lesions can
form in areas where pressure is frequently applied to the skin. Frequent
rubbing and touching of skin lesions should be avoided.
Men who shave and
who have acne can try electric and safety razors to see which is more
comfortable. Men who use a safety razor should use a sharp blade and soften
their beard thoroughly with soap and water before applying shaving cream.
Nicking blemishes can be avoided by shaving lightly and only when necessary.
A suntan or sunburn
that reddens the skin can make blemishes less visible and make the skin
feel drier for a little while. But the benefits are only temporary. The
sun can seriously damage skin, promote aging of skin, and cause skin cancer.
Furthermore, many of the medications used to treat acne make a person
more prone to sunburn.
People being treated
for acne often need to change some of the cosmetics they use. All cosmetics,
such as foundation, blush, eye shadow, and moisturizers, should be oil
free. Patients may find it difficult to apply foundation evenly during
the first few weeks of treatment because skin may be red or scaly, particularly
with the use of topical tretinoin or benzoyl peroxide. Lip products that
contain moisturizers may cause small, open and closed comedones to form.
Hairstyling products that come in contact with the skin along the hairline
can cause burning or stinging in people with acne. Products that are labeled
as noncomedogenic (do not promote the formation of blemishes) should be
used; in some people, however, even these products may cause acne.
Research Is Being Done on Acne?
are working to develop new topical antibiotics for treating acne to replace
some of those in current use. As with many other types of bacterial infections,
doctors are finding that, over time, the bacteria that cause acne are
becoming resistant to treatment with certain antibiotics. A different
type of antibiotic or a stronger one is needed to kill disease-causing
bacteria once they become resistant to existing antibiotics.
Research is being
conducted on lipophilic compounds, a class of drugs that are potent in
decreasing inflammation and killing P. acnes. Additional research
is also being conducted on the potential side effects of isotretinoin
and the long-term use of medications used for treating acne.
are attempting to determine the factors in girls during early puberty
that might predict the development of severe acne later. Finally, some
researchers are studying how acne affects certain aspects of patients’
lives, including psychological health and quality of life.
Can People Find More Information on Acne?
- American Academy
P.O. Box 4014
Schaumburg, IL 60168–4014
Fax: (847) 330–0050
World Wide Web address: http://www.aad.org/
This national organization
for dermatologists publishes a brochure on acne. The brochure can be obtained
by calling or writing to the academy; it is also available on the organization’s
Web site. The academy can also provide referrals to dermatologists.
- National Arthritis
and Musculoskeletal and Skin Diseases Information Clearinghouse
National Institutes of Health
1 AMS Circle
Bethesda, MD 20892–3675
NIAMS Fast Facts—For health information that is available 24 hours a
day by fax, call 301/881–2731 from a fax machine telephone.
World Wide Web address: http://www.nih.gov/niams/