Acne is an inflammatory skin condition characterized by clogged pores, blackheads, and pimples. The oil glands, or sebaceous glands, are connected to hair follicles and release a substance known as sebum that lubricates hair and skin. Usually, sebum travels up the hair follicle and out onto your skin. But when the sebaceous glands produce too much oil and combines with dead skin cells, the follicles become blocked and inflamed. Acne most often affects the nose, forehead, cheeks, chin, back, and trunk. Up to 45 million people have acne, making it the most common skin condition in the United States. While it tends to last longer in women, men are more likely to get acne, and to have more severe cases. Acne is most common in teens and it generally goes away by age 30. Although it is not a serious health threat, severe acne can be painful and may cause permanent scarring.

There are several types of acne lesions:

• Closed comedone (whitehead), a clogged follicle. Whiteheads usually appear on the skin as small, round, white bumps.
• Open comedone (blackhead), a plugged follicle that opens and turns dark at the surface of the skin. Blackheads do not indicate the presence of dirt.
• Papules, inflamed lesions that appear as small, pink bumps on the skin.
• Pustules (pimples), inflamed pus-filled lesions that are red at the base.
• Cysts and nodules, large, inflamed, pus-filled lesions deep under the skin that can cause pain and scarring.
• Greasiness (only skin)

Lesions can cause scars ranging from small, sunken pits to large elevated blemishes, depending on how severe the acne is and what your skin type is.

Acne is caused by the combination of too much sebum and a buildup of dead skin cells. No one knows what causes excess sebum production. In teens, rising hormone levels may be a factor. Too much sebum blocks hair follicles, and small bacteria-filled cysts called comedones form. If these comedones do not rupture, they develop into whiteheads or blackheads. When comedones rupture, the inflammation can spread into the surrounding area. Papules, pustules, cysts, and nodules are types of inflammatory lesions. Acne may be associated with certain endocrine disorders, nonendocrine diseases, and the use of certain medications. Acne is also exacerbated by certain environmental factors, such as hot, humid climate, certain medicines (such as steroids), and industrial exposure to certain chemicals.

The following may cause or worsen acne:

• Family history of acne
• Being a teenager (85% of teenagers are affected; highest incidence between ages 16 to 18)
• Using oily cosmetic or hair products containing vegetable or animal fats
• Hormonal changes common during adolescence, pregnancy, or menstruation (acne tends to flare up 2 to 7 days before menstruation begins)
• Certain medicines, such as corticosteroids, androgens, oral contraceptives, lithium, halogens, isoniazid, phenytoin, phenobarbital, and high levels of iodine (such as from kelp)
• Sweating and friction on your skin, caused by headbands, back packs, bicycle helmets, or tight collars
• Squeezing and picking comedones
• Certain conditions, such as polycystic ovarian syndrome

Acne is rarely a serious health problem. General practitioners and internists can treat most people with mild-to-moderate forms of acne. People with more severe cases are often referred to a dermatologist. Your doctor will take a complete medical history that includes questions about:

• Skin care, cosmetic use, and diet
• Factors that trigger flare ups
• Medicine use
• Prior treatment

Your doctor will also examine your face, chest, back, and other areas for blemishes, lesions, and scars.

Treatment is aimed at reducing sebum production, helping the skin shed dead cells so they do not build up, and preventing bacteria from accumulating. Early treatment is essential to prevent scarring. You can help by doing the following:

• Wash skin once or twice a day with a mild cleanser. Washing more often, scrubbing skin, or using facial masks can make acne worse.
• Use oil-free skin care products and cosmetics. Look for products that say "water based" or "non comedogenic."
• Try over-the-counter lotions containing benzoyl peroxide or salicylic acid.
• People with mild cases of acne may reduce symptoms with herbs, Ayurveda, or homeopathy. You may have to use medicines or complementary and alternative remedies for at least 6 to 8 weeks before seeing a noticeable improvement in symptoms.

Drug Therapies

Topical

Topical formulations are usually the first line therapy for acne. They are used to prevent and treat acne. Your doctor may also prescribe topical medicines to treat acne. The most commonly used include:

• Retinoids (tretinoin or Retin-A, adapalene or Differin, and tazarotene or Tazorac). These are medicines derived from vitamin A that work by unclogging pores and reducing inflammation. Side effects may include redness, peeling, and photosensitivity (high risk of sunburn). Most retinoids are applied at night. Pregnant women should not use topical retinoids during pregnancy. Acne may worsen during the first 3 to 4 weeks of retinoid therapy before improving.
• Antibiotics. Antibiotics work by killing bacteria and reducing inflammation. Topical antibiotics, such as clindamycin or erythromycin, are available in prescription form. They may be used to treat mild-to-moderate acne.
• Benzoyl peroxide. Benzoyl peroxide is also available in prescription form. Benzoyl peroxide may irritate the skin and cause peeling. Water-based formulations of the lowest strength are least irritating.

Your doctor may recommend a combination of topical medicines, such as benzoyl peroxide and clindamycin, or tretinoin (a retinoid) and clindamycin. Older topical preparations, such as sulfur, resorcin, and salicylic acid are still useful, particularly when newer medicines are not well tolerated.

Oral

Your doctor may prescribe oral (taken by mouth) antibiotics either alone or in addition to topical medications for moderate-to-severe acne. For those with severe, inflammatory acne that does not improve with other medications, an oral retinoid called isotretinoin (Accutane) may be prescribed.

• Antibiotics. Antibiotics work by killing bacteria and reducing inflammation. Commonly prescribed oral antibiotics include doxycycline, minocycline, and tetracycline. Pregnant women and children younger than 9 should not take these antibiotics. Side effects may include gastrointestinal upset and vaginal itching.
• Isotretinoin (Accutane). Doctors are not sure exactly how isotretinoin works, although it may reduce the production of sebum. It is usually prescribed for people with severe, inflammatory acne that does not get better with other medicines. Isotretinoin is taken twice a day for 20 weeks. It causes severe birth defects and must not be used by pregnant women, or those who may become pregnant. In fact, in the U.S. women who take isotretinoin are required to undergo regular pregnancy tests and take some form of prescription birth control. Isotretinoin also has many side effects, some potentially serious, that warrant limiting its use to serious cases of acne.

Some women may be prescribed birth control pills that seem to reduce acne.

Surgery and Other Procedures

Surgery or other procedures may help improve the appearance of skin scarred by acne. Chemical peeling (where a chemical solution is applied to the skin that causes it to blister and eventually peel off) can reduce minor scars. Dermabrasion (a procedure that uses a rapidly rotating brush to remove the top layers of skin) can help more severe scarring. Laser resurfacing uses pulses of light to remove the top layer of skin and reduce scarring. However, few studies have compared light and laser therapy with conventional acne treatments.

Complementary and Alternative Therapies

Complementary and alternative therapies (CAM) may play a role in the treatment of acne. You should work with a knowledgeable provider and inform all of your physicians about any CAM therapies you are planning on using. Some CAM therapies may interfere with conventional treatments and may not be right for every person.

Nutrition

Some studies suggest that foods with a high gycemic load, such as processed snacks, refined sugar, and baked goods, may exacerbate acne. Dairy intake also appears to be weakly associated with acne. A low glycemic diet helps keep blood sugar stable and under control. Food allergies may also play a role in adult acne, and people may want to avoid foods that appear to make their symptoms worse.

• Zinc (30 mg, 2 times per day for a month, then 30 mg per day). Several studies indicate that the mineral zinc may reduce the effects of acne. However, high doses of zinc can cause anemia, vomiting, and immune system suppression. It also interacts with tetracycline, which is often prescribed for acne. Taking more than 100 mg of supplemental zinc daily, or taking supplemental zinc for 10 years or more, doubles the risk of developing prostate cancer. There is also concern that taking large amounts of a multivitamin plus a separate zinc supplement increases the chances of dying from prostate cancer. For these reasons, talk to your doctor before taking zinc. Zinc can interfere with some medicines and other minerals, including certain antibiotics, and potentially Cisplatin. Speak with your doctor.
• Niacinamide (as a 4% topical gel). One study found that applying a 4% niacinamide gel to the skin twice daily for 2 months significantly improved acne symptoms. However, the study lacked a placebo, so it is hard to say how effective topical niacinamide might be on its own.
• L-carnitine. Researchers in Greece showed that, among a large group of people, mild side effects from isotretinoin (Accutane), such as dry skin, chapped lips, dry eyes, and nosebleeds caused by dry nose, improved when taking L-carnitine compared to those who took a placebo. L-carnitine may interfere with some medicines, including thyroid hormone, warfarin (Coumadin), and Acenocoumarol (Sintrom). L-carnitine may increase the risk of seizures in people who have previously had seizures.
• Vitamin A. Vitamin A has many of the same properties as the retinoid drugs, but often with fewer side effects. Few studies have been done on vitamin A and acne, however. Too much vitamin A can be toxic, so talk to your doctor to determine the right dose for you, and only take high doses of vitamin A under a doctor's supervision. It is especially important that you do not combine vitamin A supplementation and retinoid medicines for acne. DO NOT take extra vitamin A if you are pregnant or have liver disease.

Herbs

Herbs may help strengthen and tone the body's systems. As with any therapy, you should work with your health care provider before starting treatment. You may use herbs as dried extracts (capsules, powders, or teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, make teas with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots. Drink 2 to 4 cups per day. You may use tinctures alone or in combination as noted.

• Tea tree oil (Melaleuca alternafolia, 5% gel). Applied to the skin, tea tree oil may help reduce bacteria, reducing inflammation and improving symptoms. One study compared the effectiveness of tea tree oil gel with benzoyl peroxide lotion in 119 people with mild-to-moderate acne. People in both groups improved, and the people using tea tree oil reported fewer side effects (including stinging, itching, burning, and dryness) than those using benzoyl peroxide.
• Guggul (Commiphora mukul, dose equivalent to 25 mg guggulsterones or about 500 mg of guggul, 2 times per day). In one study, taking guggul orally had the same effect as taking tetracycline. You should not take guggul if you are pregnant or nursing. Guggul may have estrogen-like effects, and should not be taken by anyone with a history or family history of hormone-related cancers, including prostate, breast, or ovarian cancer. In addition, the herb may interact with anticoagulants (blood-thinning medicines), tamoxifen, and birth control pills containing estrogen, as well as herbs that have estrogen-like effects (such as black cohosh, licorice, soy, and others). People who take these herbs or drugs should not take guggul. Guggul can slow blood clotting, and may increase the risk of bleeding in those with bleeding disorders, or those who take blood-thinning medicines, such as warfarin (Coumadin) and aspirin.
• Ayurvedic medicine. Ayurvedic medicine may help improve symptoms. More studies are needed. In one study, a combination of ginger(Zingiber officinale), Holarrhena antidysenterica, and Embelia ribes reduced the number of inflammatory and noninflammatory lesions. In another study, combined oral and topical use of Aloe barbadensis, Azardirachta indica, turmeric (Curcuma longa), Hemidesmus indicus, Terminalia chebula, Terminalia arjuna, and ashwagandha (Withania somnifera) also reduced the number of lesions. Some of these herbs may have side effects, or may interact with certain medicines. Speak with your physician.

Homeopathy

Few studies have examined the effectiveness of specific homeopathic remedies. Professional homeopaths, however, may recommend one or more of the following treatments for acne based on their knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. In homeopathic terms, a person's constitution is his or her physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual.

• Belladonna, for people who experience flushes of heat to the face, or who have inflamed pustular acne that improves with cold applications
• Calendula, for skin conditions involving pustules or blisters
• Hepar sulphur, for painful, pus-filled acne
• Kali bromatum, for deep acne, especially on the forehead, in people who are chilled and nervous
• Silicea, for pustules or pit-forming acne

Pregnancy

Pregnant women should avoid all retinoids (those either taken by mouth or applied to the skin), isotretinoin (Accutane), and the antibiotics tetracycline, minocycline, and doxycycline because they can be harmful to the fetus. The antibiotic erythromycin (either applied to the skin and taken by mouth) is safe to use during pregnancy.

Prognosis and Complications

Acne is not a serious health threat, but severe acne can be painful, emotionally upsetting, and may cause permanent scarring. Squeezing lesions can rupture comedones and cause inflammation. Symptoms generally diminish after adolescence and disappear by age 30. However, adult acne, especially in women, seems to be increasing and is not unusual in women in their 30s, 40s, and beyond.

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