Author: Reviewed and updated by Dr Amanda Oakley Dermatologist, Hamilton, New Zealand; Vanessa Ngan, Staff Writer; and Clare Morrison, Copy Writer; June 2014.
Most people with spots have a medical condition called acne vulgaris. Vulgaris is the medical term for "common". It is given this name to distinguish it from less common variants of acne (see all the acne types).
You may prefer to call acne "pimples", "spots" or "zits".
Nearly all of us have acne at some time or another. It mainly affects adolescents (and can start as young as 8 years old), but acne may persist, begin or become more severe in adulthood.
Find out more about the causes of acne...
Acne most often affects the face, but it may spread to involve the neck, chest and back, and sometimes even more extensively over the body.
Individual lesions are centred on the pilosebaceous unit, ie the hair follicle and its associated oil gland. Several types of acne spots occur, often at the same time. They may be inflamed papules, pustules and nodules; or non-inflamed comedones and pseudocysts.
Individual acne lesions usually last less than 2 weeks but the deeper papules and nodules may persist for months. Many acne patients also have oily skin (seborrhoea).
More images of acne ...
Acne may be classified as mild, moderate or severe. Comedones and inflammatory lesions are usually considered separately.
Some dermatologists assess the severity of a patient's acne more precisely by using a grading scale. The inflammatory lesions are compared with a set of standard photographs to determine the grade, which may be 1 (very mild) to 12 (exceptionally severe) for example.
In clinical trials evaluating acne treatment, the numbers of uninflamed and inflamed lesions are carefully counted at regular intervals. It is remarkably difficult to count consistently.
Treatment for acne depends on the patient's age and sex, the extent and the severity of the acne, how long it has been present, and response to previous treatments.
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