Acne vulgaris (common acne): Commonly referred to 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.
Benzoyl peroxide: This is available in both over-the-counter and prescription treatments; Benzoyl peroxide is used as a topical treatment for acne as well as a bleaching agent for flour, fats, waxes and oils. In acne treatment, it acts as an antiseptic and oxidizing agent, reducing the number of blocked pores but can bleach the skin and fabric if used incorrectly.
Blackhead (also called open comedo): A plugged pore that enlarges and pushes through the surface of the skin. The dark color is due to a buildup of natural occurring dark pigment found in skin.
Comedo (comedones): This is the beginning of every type of acne lesion. When dead skin cells mix with sebum and get trapped in the opening of a follicle, this is called a comedo (a plugged pore or clogged follicle).
Cyst (also called nodule): A deep inflammatory lesion in the skin, often leading to scarring.
Follicle: Also called "pores," tiny holes in the skin that contains the fine hairs that cover our faces and bodies. Each follicle has oil glands that produce sebum, which travels up the hair shaft and out onto the surface of the skin.
Inflammatory: Anything that stimulates inflammation, pain, swelling, redness and heat. The inflammation is the reaction of the skin to injury, infection, or irritation caused by clogged follicles.
Keloid: A red, raised formation of fibrous scar tissue caused by excessive tissue repair in response to trauma or surgical incision.
Lesion: An abnormality in the skin.
Macules: flat, reddish spots that are the final stage of most inflamed acne lesions. After an inflamed acne lesion flattens, a macule may remain for up to 6 months. When the macule eventually disappears, no trace of it will remain.
Nodule (also called cyst): Nodules develop when the contents of a comedo have spilled into the surrounding skin and the local immune system responds, producing pus. Usually large and very painful, nodules are inflamed, pus-filled lesions lodged deep within the skin. It is the most severe form of acne lesion, and may persist for weeks or months. Both nodules and cysts often leave deep scars.
Papule: This is the mildest form of inflammatory acne and appears on the skin as a small, firm pink bump. This elevation of the skin does not contain pus but can be sore and tender.
P. acnes: (AKA: Propionibacterium acnes): Part of the skin's natural sebum maintenance system, the bacterium Propionibacterium acnes (P. acnes for short) is a regular resident of all skin types. Once a follicle is plugged the P. acnes bacteria multiply rapidly, starting the inflammation in the follicle and surrounding skin.
Pustule: A pimple; small inflamed elevation of the skin that is filled with pus. They are normally red at the base, with a yellowish or whitish center. Pustules do not contain a great deal of bacteria, and the inflammation is caused by chemical irritation from sebum components such as fatty free acids.
Retinoid: Any of various natural or synthetic derivatives of vitamin A.
Sebaceous glands: Oil-producing glands at the base of every sebaceous hair follicle. These glands continue to produce oil even after the pores are clogged.
Sebum: The oily substances produced by sebaceous glands, composed of cholesterol and free fatty acids. Sebum travels up the hair shaft and onto the skin's surface, keeping it soft and pliable.
White blood cells: White blood cells are your body's "Defense System." When your body encounters unwanted bacteria, it uses the white blood cells to fight the trespasser. This process is called chemotaxis or the inflammatory response. In acne, it causes pimples to become red, swollen and painful.
Whitehead (also called closed comedo): When a 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, white bumps.