What Is Acne?

Acne is a disorder resulting from the action of hormones and other substances on the skin's oil glands (sebaceous glands) and hair follicles. These factors lead to plugged pores and outbreaks of lesions commonly called pimples or zits. Acne lesions usually occur on the face, neck, back, chest, and shoulders. Although acne is usually not a serious health threat, it can be a source of significant emotional distress. Severe acne can lead to permanent scarring.

How Does Acne Develop?

Doctors describe acne as a disease of the pilosebaceous units (PSUs). Found over most of the body, PSUs consist of a sebaceous gland connected to a canal, called a follicle, that contains a fine hair (see "Normal Pilosebaceous Unit" diagram). These units are most numerous on the face, upper back, and chest. The sebaceous glands make an oily substance called sebum that normally empties onto the skin surface through the opening of the follicle, commonly called a pore. Cells called keratinocytes line the follicle.

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Part 1: What is acne?

Part 2: What is acne? ...continued

Part 3: What causes acne?

Part 4: How is acne treated?

Part 5: How should I care for my skin?

Part 6: Current research for acne?

Source: Adapted from National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)