Glossary
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Acne conglobata. This rare but serious form of inflammatory acne develops primarily on the jawline, cheeks, back, buttocks and chest. In addition to the presence of pustules and nodules, there may be severe bacterial infection as nodules become connected to one another deep beneath the surface of the skin. If not treated, acne conglobata can lead to scarring.
Acne cosmetica. A relatively mild form of acne triggered by topical make-up products, acne cosmetica typically consists of small pink bumps and local inflammation on the cheeks, chin and forehead. It may develop over the course of a few weeks or months and can persist indefinitely. It usually does not cause scarring.
Acne vulgaris. Commonly referred to simply as “acne,” this skin condition affects 90% of all adolescents and 50% of adult women. It is caused by the clogging of tiny hair follicles on the face and body, and is characterized by unsightly and often painful lesions on the surface of the skin and below. Contrary to popular belief, acne is not caused by dirt, but by five factors working together: Hormones, extra oil production, uneven skin shedding, bacteria and inflammation.
Allantoin. An active skin protectant used for its healing, softening and moisturizing properties. Derived from comfrey, allantoin stimulates healthy tissue growth and acts as an anti-irritant.
Androgens. Hormones that begin production at puberty in both males and females. Androgens stimulate the production of sebum, which is why nearly everyone experiences some acne lesions during adolescence.
Anti-androgen. Any substance that inhibits the body’s production of androgens, either in the ovaries or the adrenal gland. Oral contraceptives are often used to treat acne in this fashion, in combination with other drugs such as spironolactone, a common diuretic with anti-androgenic properties.
Antibiotics. Antibiotics control acne by curbing the body’s production of P. acnes and decreasing inflammation. For patients with mild acne, topical antibiotics (creams, gels, pads and lotions applied directly to the skin) may have some success, but these are limited in their ability to penetrate deep into the follicle. For those who suffer from moderate to severe acne, doctors may prescribe a combination of topical remedies and oral antibiotics.
Atrophic macules. Atrophic macules, a form of scarring most \common in Caucasians, are soft with a slightly wrinkled base. Blood vessels just below the surface of the scar may make them appear purplish when they are recent, but this discoloration may fade over time to a pale ivory. Atrophic macules are usually small when they occur on the face, but may be a centimeter or larger elsewhere on the body.
Benzoyl peroxide. Available in both over-the-counter solutions and prescription treatments, benzoyl Peroxide works by destroying P. acnes, the bacteria that causes the condition acne. It acts as an antiseptic and oxidizing agent, reducing the number of blocked pores. In 80 years of use, there has been no bacterial resistance to benzoyl peroxide; it is the cornerstone of acne therapy.
Blackhead (or open comedo). A blocked pore in which the “plug” enlarges and pushes through the surface of the skin. The plug’s dark appearance is not due to dirt, but rather to a buildup of melanin, the skin’s dark pigment.
Closed comedo (or whitehead). If the plug in the follicle stays below the surface of the skin, the lesion is called a closed comedo, or whitehead. These usually appear on the skin as small, whitish bumps.
Comedo (plural: comedones). When dead skin cells mix with sebum and get trapped in the opening of a follicle, this is a comedo – the raw material for every kind of acne lesion. It acts like cork in a bottle, trapping dirt, bacteria and sebum inside the follicle, eventually resulting in an acne lesion.
Comedogenic. Substances that are likely to clog your pores.
Contraceptives. Birth control pills (combinations of estrogen and progesterone) are often prescribed for hormonal acne; the estrogen helps suppress the androgens produced by the ovaries. Currently, just two formulas, Ortho Tri-Cyclin and Estro-Step, have been approved by the FDA for the treatment of acne – but many formulas are just as effective.
Corticosteroids. Small doses of corticosteroids, like prednisone or dexamethasone, may be used to treat acne. They work by curbing inflammation and suppressing the androgens produced by the adrenal glands. Long-term use of prednisone can cause a stubborn form of acne; corticosteroids are most affective when used in combination with oral contraceptives.
Cortisol. Produced by the adrenal glands in response to stress, the hormone cortisol stimulates the sebaceous glands, triggering the production of extra oil. This increases the incidence of comedones, causing acne breakouts.
Cyst. See nodule
Dandruff (seborrheic dermatitis). Persistent flaking, scaling or itching of the scalp. For dandruff sufferers, the natural process of scalp-cell renewal is accelerated when fighting off P. ovale, a normal fungus found on every human head. This causes dead cells to slough more quickly, creating the symptoms we know as dandruff.
Demodex mites. Normal residents of human skin, these microscopic creatures are five times more prevalent in patients with rosacea; they are believed to contribute to irritation and flushing in patients with this condition.
Dermatitis (or eczema). Dermatitis (or Eczema) is characterized by a rapidly spreading red rash which may be itchy, blistered and swollen. Atopic dermatitis is related to asthma and hay fever-type allergies, and is often seen in early childhood. Contact dermatitis is usually caused by contact with irritants (detergents or harsh chemicals) or allergens (substance to which the patient is allergic, like rubber, preservatives or a particular fragrance). Individuals with chronic dermatitis will have a longstanding history of irritation in the affected area or areas – the eyelids, neck and hands are most commonly affected in adults. Dermatitis may come and go throughout a person’s life.
Dermatologic surgery. Surgery to repair or improve the function or cosmetic appearance of skin tissue. Methods include laser surgery, cryosurgery, chemical surgery, aspirational surgery (for scarring) and excisional surgery (for acute cysts or nodules). In cases of severe acne scarring, dermatological surgery can be helpful in improving the appearance of some scars.
Dermis. The second layer of the skin, which serves as a foundation for the epidermis and makes up the principle mass of the skin. This layer produces collagen, elastin and reticulin, the substances that lend structure and support to your largest organ. The dermis also houses nerve endings, blood vessels, oil glands and sweat glands.
Epidermal Cyst. A sac-like growth in the deeper layers of the skin, filled with a soft whitish material. This substance, which is composed of fatty acids and oils, may have an unpleasant odor. In patients with a history of acne, epidermal cysts may occur on the face, scalp and trunk. They are often permanent; even if the material is extracted, the sac remains and the cyst may return. In these cases the entire cyst sac must be excised to prevent recurrence.
Epidermis. The top layer of the skin, which acts as your body’s natural suit of armor. The epidermis is made up of corneocytes (the outermost layer of dead skin cells), melanocytes (which produce melanin, the substance that gives your skin its color), and Langerhan cells (which work with the immune system to help you fight off disease).
Favre-Racouchet Syndrome. A skin condition afflicting men and women over 50 causing large blackheads around the eyes and on the upper cheeks. Unlike acne blackheads, Favre comedones do not regress if left untreated; they must be surgically extracted or treated with topical retinoids.
Follicle (or sebaceous follicle). Also called “pores,” these tiny holes house the fine hairs that cover our faces and bodies. Oil glands at the base of each follicle are working to produce sebum, which travels up the hair shaft and out onto the surface of the skin.
Follicular macular atrophy. A form of acne scarring characterized by small, soft white lesions resembling whiteheads that didn’t fully develop; they may persist for months or years. This kind of scarring is more likely to occur on the chest or back.
Ice-pick scars. Most often found on the cheek, ice-pick scars are usually small but deep, with a jagged edge and steep sides. Over time, ice-pick scars may evolve into depressed fibrotic scars. These also have sharp edges and steep sides, but are larger and firm at the base.
Inflammatory. A word that means “causing inflammation.” In acne, “inflammatory” is usually used to describe lesions that are inflamed by chemical reactions or bacteria in clogged follicles.
Isopropyl alcohol. A common ingredient of many facial toners, isopropyl alcohol is a strong astringent that can strip the skin of necessary oils – leaving it dry and irritated.
Isotretinoin (Accutane). The “big gun” in acne therapy, Accutane is used to treat severe inflammatory acne when other treatments fail. The drug reduces sebum production by as much as 85-90% and has a high rate of success for improving acne.
Keloid. A type of hereditary scarring that occurs more frequently in African-American, Asian and Latino populations. Keloid scarring occurs when the skin cells respond to injury by producing an excess of collagen, which forms into lumpy fibrous masses. These scars appear firm and shiny, and may persist for years.
Keratosis pilaris. Patches of tiny, red, kernel-hard bumps on the cheeks, chest, backs of the arms, shoulders, buttocks and the front of the thighs. Most commonly found in teenagers, keratosis pilaris occurs when hair follicles become clogged with dead skin cells that are not properly sloughed off. It is usually painless and feels spiny to the touch.
Macule. The flat, reddish spots that are the final stage of an acne lesion. Macules may last for up to six months (longer with prolonged sun exposure) but usually leave no permanent scar.
Melasma (or cholasma). Localized hyperpigmentation (brownish blotches) that appear most commonly in women who are pregnant or taking oral contraceptives. These are worsened by exposure to the sun, and can be treated with topical bleaching agents. Rarely, women who are neither pregnant nor taking birth control pills – and occasionally men – may get melasma.
Microcomedo. The first stage of comedo formation; a comedo so small that it can be seen only with a microscope.
Milia. Tiny cysts found mostly in the area around the eyes. They are hard to the touch and deep in the skin. Milia may last for weeks or even months; if they are particularly troublesome to you, consult your dermatologist for professional, safe removal.
Nodule. Large and usually very painful, nodules are inflamed, pus-filled lesions lodged deep within the skin. Nodules develop when the contents of a comedo have spilled into the surrounding skin and the local immune system responds, producing pus. The most severe form of acne lesion, nodules may persist for weeks or months, their contents hardening into a deep cyst. Both nodules and cysts often leave deep scars.
Noncomedogenic. Substance that is not likely to clog the pores.
Noninflammatory. In acne, lesions that are not associated with redness in the skin
P. acnes. See Propionibacterium acnes.
Papule. The mildest form of inflammatory acne is the papule, which appears on the skin as a small, firm pink bump. These can be tender to the touch, and are often considered an intermediary step between non-inflammatory and clearly inflammatory lesions.
Papulopustular. A type of acne characterized by the presence of papules and pustules.
Peri-Oral Dermatitis. Primarily affecting women in their 20s and 30s, this condition is characterized by patches of itchy or tender red spots around the mouth. The skin bordering the lips may appear pale and dry, while the chin, upper lips and cheeks become red, dry and flaky. It can also affect the skin around the nose.
Pore. See Follicle.
Post-inflammatory hyperpigmentation. A darkening of the skin at the site of a healing acne lesion. Most prevalent in African-American, Asian and Latino populations, these spots can last up to 18 months – but may disappear more quickly if you stay out of the sun.
Propionibacterium acnes. The bacterium Propionibacterium acnes (P. acnes for short) is a regular resident of all skin types; it’s part of the skin’s natural sebum maintenance system. Once a follicle is plugged, however, P. acnes bacteria multiply rapidly, creating the chemical reaction we know as inflammation in the follicle and surrounding skin.
Pseudofolliculitis barbae. The acne-like breakouts commonly called “shaving bumps.” As hairs begin to grow back after shaving, waxing or plucking, they get trapped inside the follicle and cause irritation and swelling. Shaving bumps are more common among people with curly hair.
Puberty. The time of life when a child begins the process of physical maturation. Onset is usually in the early teens and is accompanied by a large increase in hormone production – and acne.
Pustule. Small, round acne lesions that are clearly inflamed and contain visible pus. They may appear red at the base, with a yellowish or whitish center. Pustules do not contain a great deal of bacteria; the inflammation is caused by chemical irritation from sebum components such as fatty free acids.
Retinoids. Chemically related to Vitamin A, retinoids regulate growth of epithelial cells (skin, lung, and gut) and are often powerful antioxidants and cancer preventing agents. Retinoids are also found in many acne mediations, such as Retin-A and Renova; they help dissolve comedones and encourage normal skin-cell sloughing and renewal.
Rosacea. Found in adults between 30 and 60 years of age, rosacea is an acne-like condition that appears only in areas that are likely to flush when we’re embarrassed, excited or hot – primarily the face, neck and chest. The skin is bumpy, red and oily in appearance, and may also involve papules and pustules.
Salicylic acid. Salicylic acid is a mild acid that works as a keratolytic agent – it encourages the sloughing of dead skin cells. It stimulates the peeling of the top layer of skin and the opening of plugged follicles, which helps reestablish the normal skin-cell replacement cycle. For milder acne, salicylic acid helps unclog pores to resolve and prevent lesions.
Sebaceous follicle. See Follicle.
Sebaceous glands. Oil-producing glands at the base of every sebaceous hair follicle – the tiny holes commonly called pores. Found on the face, neck, back and chest, these follicles are the sites of acne lesions.
Sebum. The oily substance produced by sebaceous glands, composed of cholesterol and free fatty acids. Sebum travels up the hair shaft and is expelled onto the skin’s surface, keeping it soft and pliable.
Sloughing (SLUFF-ing). Part of the skin’s natural renewal process, sloughing is the act of shedding dead skin cells to make room for new ones. When cells die, they travel up the hair follicle and out onto the surface of the skin, where they are gradually rubbed away or released into the environment. Until we reach our early 30s, the sloughing and renewal process takes about 28 days. As we age the process begins to slow; by the time we reach our 40s, complete skin renewal may take more than 50 days.
Soft scars. A type of acne scar with gentle, sloping rolled edges that merge with the surrounding skin. They are usually small, circular or linear in shape, and soft to the touch.
Subcutaneous fat. The bottom layer of your skin is composed primarily of fat cells. This part of your skin acts as an insulator, keeping you warm and protecting underlying tissue from shocks and bumps. It’s also the place where your hair begins – each hair follicle all over your body has its roots in the subcutaneous layer.
White blood cells. White blood cells are your body’s “Critical Response Unit.” When your body encounters unwanted bacteria, it sends an army of white blood cells to attack the intruders. This process is called chemotaxis or the inflammatory response. In acne, it causes pimples become red, swollen and painful.
Whitehead. See closed comedo.
Witch hazel. A gentle astringent anti-inflammatory and healing properties. Helps to tighten pores and remove excess oil.
