Acne is a common inflammatory skin disease characterized by pimples on the face, chest, and back. It occurs when the pores of the skin become clogged with oil, dead skin cells, and/or bacteria.
Acne vulgaris, the medical term for common acne, is the most common skin disease. It affects nearly 17 million people in the United States. While acne can arise at any age, it usually begins at puberty and worsens during adolescence. Nearly 85% of people develop acne some time between the ages of 12 and 25 years old. Up to 20% of women develop mild acne. It is also found in some newborns.
The sebaceous glands lie just beneath the skin's surface. They produce sebum, an oily secretion that helps to preserve the flexibility of the hair and moisturizes the skin. These glands and the hair follicles within which they are found are called sebaceous follicles. These follicles open onto the skin through pores that allow the sebum to reach the hair shaft and the skin. In certain situations, the glands excrete excess sebum and it cannot be cleared from the pores efficiently. This happens, for instance, at puberty when increased levels of the androgen hormones cause overproduction of sebum. In addition, cells lining the follicle are shed too quickly and begin to clump together. The excess sebum combines with the dead cells and forms a plug, or comedo (also called comedones), that blocks the pore, which is not usually seen. When the follicle begins to bulge and show up as a small whitish bump mostly under the skin, it is called a whitehead. If the comedo opens up, the top surface of the plug darkens, and it is referred to as a blackhead.
Infection results when a plugged follicle is invaded by Propionibacterium acnes, a bacteria that normally lives on the skin, and possibly other microorganisms. The bacteria produce chemicals and enzymes that bring on inflammation. Pimples are the result of infected blackheads or whiteheads that rupture, releasing sebum, bacteria, dead skin, and white blood cells onto the surrounding tissues. Inflamed pimples near the skin's surface are called papules; they are red and raised, and may be quite tender to the touch. The papules may become filled with pus, and are then called pustules. If the follicle continues to enlarge rather than rupture, it forms a closed sac, called a cyst, which can be felt as a lump under the skin. Large hard swellings deep within the skin
are called nodules. Both nodules and cysts may cause pain and scarring.
Causes & symptoms
The exact cause of acne is mostly unknown. Sometimes when acne in women is due to excess male hormone production, it is diagnosed by an onset of the condition in adulthood; excessive growth of hair, especially in places not usual on a female, called hirsuitism; irregular menstrual cycles; and premenstrual flare-ups of acne. A 2001 study demonstrated that menstrual cycle does affect acne. Surprisingly, the study revealed that 53% of women over age 33 experienced a higher premenstrual acne rate than women under age 20.
Many alternative practitioners assert that acne is often related to a condition of toxicity in the intestines or liver. This may be due to the presence of bacteria such as Clostridia spp. and Yersinia enterocolitica, a low-fiber diet; a lack of friendly gut flora such as Lactobacillus spp.; an intestinal overgrowth of Candida albicans; and food allergies.
The interaction between the body's hormones, skin protein, skin secretions, and bacteria determines the course of acne. Several other factors have also been shown to affect the condition:
- Age. Teenagers are more likely than anyone to develop acne.
- Gender. Boys have more severe acne and develop it more often than girls.
- Disease. Hormonal disorders can complicate acne in girls.
- Heredity. Individuals with a family history of acne have greater susceptibility to the condition.
- Hormonal changes. Acne can flare up before menstruation, during pregnancy, and menopause.
- Diet. Although they are not the primary cause of acne, certain foods may bring on flare-ups or make the condition worse.
- Drugs. Acne can be a side effect of antibiotics, oral contraceptives, and anabolic steroids.
- Personal hygiene. Use of abrasive soaps, hard scrubbing of the face, or handling pimples will often make them worse.
- Cosmetics. Oil-based makeup and hair sprays worsen acne.
- Environment. Exposure to oils and greases, polluted air, and sweating in hot weather can all aggravate acne.
- Stress. Emotional stress may contribute to acne.
- Friction. Continual pressure or rubbing on the skin by such things as bicycle helmets, backpacks, or tight clothing, as well as hard scrubbing of the skin, can worsen acne.
The most common sites of acne are the face, chest, shoulders, and back, since these are the parts of the body where the most sebaceous follicles are found. In teenagers, acne is often found on the forehead, nose, and chin. As people get older, it tends to appear towards the outer part of the face. Adult women may have acne on their chins and around their mouths. The elderly often develop whiteheads and blackheads on the upper cheeks and skin around the eyes. Inflamed lesions may cause redness, pain, tenderness, itching, or swelling in affected areas.
Acne has a characteristic appearance and is, therefore, not difficult to diagnose. A complete medical history should be taken, including questions about skin care, diet, factors that improve or worsen the condition, medication use, and prior treatment. Physical examination includes the face, upper neck, chest, shoulders, back, and other affected areas. Under good lighting, the doctor can determine what types and how many blemishes are present, whether they are inflamed, whether they are deep or superficial, and whether there is scarring or skin discoloration. Blood tests are done when the patient appears to have hormonal or other medical problems. Stool tests can be helpful in determining whether there is a bacterial or yeast overgrowth contributing to the condition. Food allergy testing should also be considered.
Alternative treatments for acne focus on proper cleansing to keep the skin oil-free; intermittent fasting; eating a good diet; an elimination diet where the individual avoids alcohol, dairy products, smoking, caffeine, sugar, processed foods, and foods high in iodine, a mineral which appears to contribute to acne.
Supplementation with herbs that are blood cleansers or blood purifiers is recommended. These herbs strengthen the action of the liver and the kidneys, helping with detoxification and excretion. Dandelion root tincture (Taraxacum officinale) is recommended. Others include burdock root (Arctium lappa), also known as gobo, and can be purchased fresh at health food grocers or in Asian markets. It can be used either raw or cooked in salads, stir-fries, or other vegetable dishes. Burdock root tincture can also be used. Red clover (Trifolium pratense) makes a pleasant tea that can be consumed throughout the day. Milk thistle seed (Silybum marianum) can either be taken in tincture form or the seeds can be ground up and eaten in combination with hot cereal, granola, or other foods.
Other herbs useful in the treatment of acne include Echinacea spp. and goldenseal (Hydrastis canadensis). Goldenseal is particularly helpful in clearing up underlying conditions of intestinal toxicity. Herbal remedies used in traditional Chinese medicine (TCM) for acne include cnidium seed, (Cnidium monnieri), and honeysuckle flower (Lonicera japonica). Supplementation nutrients, such as essential fatty acids (EFAs), vitamin B complex, zinc, vitamin A or beta-carotene, and chromium are also recommended.
Bowel toxicity may contribute to acne flare-ups, and should be addressed. Lactobacillus acidophilus and Lactobacillus bulgaricus should be taken in yogurt or in capsules to maintain a healthy balance of intestinal flora. Goldenseal can be used to kill toxic bacteria. Allergic foods should be identified and removed from the diet. Dietary fiber, such as oats and wheat bran, beans, fruits and vegetables and their skins, and psyllium seed, should be increased in the diet. The fiber will absorb toxins and carry them through the colon to be excreted.
In addition, those with acne may want to participate in movement therapy, such as yoga or t'ai chi, or begin an exercise regimen. The person may also consider stress reduction or meditation.
Acne treatment consists of reducing sebum and keratin production, encouraging the shedding of dead skin cells to help unclog the pores, and killing or limiting bacteria. Treatment choice depends upon whether the acne is mild, moderate, or severe. Complicated cases are referred to a dermatologist, or an endocrinologist, who treats diseases of the glands and the hormones. Counseling may be necessary to clear up misconceptions about the condition and to offer support regarding the negative effect of acne on the physical appearance.
Treatment for mild acne consists of reducing the formation of new comedones with over-the-counter acne medications containing benzoyl peroxide (e.g., Clearasil, Fostex), salicylic acid (Stridex), sulfur (Therac lotion), resorcinol (Acnomel cream). Treatment with stronger medications requires a doctor's supervision. Such medications include comedolytics, which are agents that loosen hard plugs and open pores. Adapalene (Differin), the vitamin A acid tretinoin (Retin-A), and concentrated versions of salicylic acid, resorcinol, and sulfur are in this group. Topical antibiotics, such as erythromycin, clindamycin (Cleocin-T), and meclocycline (Meclan), may be added to the treatment regimen. Drugs that act as both comedolytics and antibiotics, such as benzoyl peroxide, azelaic acid (Azelex), or benzoyl peroxide plus erythromycin (Benzamycin), are also used.
After washing with a mild soap, the acne medications are applied alone or in combination, once or twice a day over the entire affected area of skin. It may take many months to years to control the condition with these medications. Possible side effects include mild redness, peeling, irritation, dryness, and an increased sensitivity to sunlight that requires use of a sunscreen.
When acne is severe and the lesions are deep, oral antibiotics may be taken daily to reduce the spread of bacteria. Tetracycline is the medication most often used. Minocycline, however, may be more preferable because it has fewer side effects. Erythromycin and doxycycline are also used, and they also have side effects, including dizziness, photosensitivity, gastrointestinal problems, and darkening of the skin. Other possible side effects include allergic reactions, yeast infections, dizziness, tooth discoloration, and folliculitis. It is necessary for antibiotics to be used for up to three months to clear up the condition.
Isotretinoin (Accutane) can be used in cases of very severe acne, or if antibiotic therapy proves unsuccessful. It may clear up resistant cysts and nodules in up to 90% of people and prevent scarring. Some do require a second course of treatment before this happens, however. Although the medication can be quite helpful, women who might become pregnant should use it with care. Isotretinoin can cause birth defects up to a month after it has stopped being used. Therefore, strict attention is paid to pregnancy tests and contraceptive requirements for women of child-bearing age who take this medication.
The course of treatment with isotretinoin lasts about four to five months. If dosage is kept low, a longer course of therapy is needed. Isotretinoin is a strong medication. Side effects are very common, mostly dryness of the eyes, genital mucosa, and lips. Other effects may include increases in cholesterol, tryglicerides, and abnormal liver enzymes. Blood tests taken each month should be monitored during the course of treatment to ensure that the medication is not causing serious harm.
Anti-androgens, drugs that inhibit androgen production, are used to treat women who are unresponsive to other therapies. Oral contraceptives such as norgestimate/ethinyl estradiol (Ortho-Tri-Cyclen) have been shown to improve acne. In late 2001, a clinical trial demonstrated that ultra low-dose birth control pills (Alesse) prove as effective in treating acne as do pills with higher doses of estrogen. Improvement may take up to four months.
Other drugs, such as spironolactone and corticosteroids, may be used to reduce hormone activity in the adrenal glands, reducing production of sebum. This is the treatment of choice for an extremely severe, but rare type of acne called acne fulminans, found mostly in adolescent males. Acne conglobata, a more common form of severe inflammation, is characterized by numerous, deep, inflammatory nodules that heal with scarring. It is treated with oral isotretinoin and corticosteroids.
Other types of treatment
Several surgical or medical treatments are available to alleviate acne or the resulting scars:
- Comedone extraction. The comedo is removed from the pore with a special tool.
- Chemical peels. Glycolic acid is applied to peel off the top layer of skin to reduce scarring.
- Dermabrasion. The affected skin is frozen with a chemical spray, and removed by brushing or planing.
- Punch grafting. Deep scars are excised and the area repaired with small skin grafts.
- Intralesional injection. Corticosteroids are injected directly into inflamed pimples.
- Collagen injection. Shallow scars are elevated by collagen protein injections.
- Laser treatments. Two types of laser treatments are proving effective in treating acne scars. Laser-treated skin heals in three to 10 days, depending on the treatment chosen.
Most dermatologists now use a combination of therapies to treat acne, depending on the individual. Results of specific treatments will vary. Acne is not a serious health threat. The most troubling aspects of this condition are the negative cosmetic effects and potential for permanent scarring. Some people, especially teenagers, become emotionally upset about their condition, and this may contribute to social or emotional problems.
Acne is not considered curable, although it can be controlled by proper treatment, with improvement possibly taking many months. Acne tends to reappear when treatment stops, but it often spontaneously improves over time. Inflammatory acne may leave scars that require further treatment.
- —Structures where pimples form. They are found within the skin and house the oil glands and hair.
There are no sure ways to prevent acne, but the following steps may be taken to minimize flare-ups:
- Gentle washing of affected areas once or twice every day.
- Avoidance of abrasive cleansers.
- Limited use of makeup and moisturizers; with avoidance of oil-based brands altogether.
- Oily hair should be shampooed often and worn up, away from the face.
- A healthy, well-balanced diet should be eaten. Fresh fruits and vegetables should be stressed, and foods that seem to trigger flare-ups should be avoided.
- The face can be washed gently, twice daily with a soap compounded of sulfur, Calendula officinalis, or other substances that are useful against acne.
- Affected areas should not be handled excessively. Pimples should not be squeezed or prodded, as this may contribute to scarring, as well as spreading the acne lesions.
- Emotional stress should be kept in check.
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