What is acne?

Dr. Jeanne Morrison, PhD
Family Practitioner
Acne is a skin condition that includes pimples and cysts found most often on the face, back, and chest. These irritations are caused when dead skin cells, bacteria, and sebum (oil) clog the hair follicles in skin. When the follicles get clogged, sebum can't leave the pores; bacteria multiply and the follicle becomes inflamed, resulting in a pimple or cyst. Acne is quite common, especially in teenagers going through puberty--increased hormone production causes increased sebum production. It can be treated with a variety of medications, including topical and oral antibiotics. Although proper skin care can also help, acne is not caused by poor hygiene.

Acne results when excess oil from overactive sebaceous glands blocks pores, trapping bacteria, dirt, and dead cells inside. Bacteria proliferate within the blocked pore, leading to an infection.

There are many types of acne lesions, including blackheads (open comedos), whiteheads (closed comedos), pimples (pustules), and cystic acne.

Hormone fluctuations that occur with adolescence or pregnancy may aggravate the condition. Acne can appear anywhere on the body, but the condition most commonly appears on areas of the skin that have large pores with abundant, active oil glands such as the face, chest, and back.

Acne is a buildup of oil, microorganisms and dead skin cells in the hair follicles under the skin. When the hair follicle ruptures, the rupture triggers an "acne cascade," which inflames surrounding tissue. Androgens are a major influence on acne because they stimulate the hormone-sensitive sebaceous glands, which produce sebum. That's why you don't see acne before puberty. In women, birth control pills can either aggravate or improve acne. This probably depends on your response to progestin, one of the hormones used in many birth control pills. Greasy hair and skin products, perspiration, headbands and other things that can plug up pores make acne worse. Stress may trigger acne flare-ups. Squeezing pimples can make acne worse and more likely to leave scars.

Continue Learning about Acne

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.