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”.

Who gets acne vulgaris?

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…

What are the clinical features of acne vulgaris?

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.

Superficial lesions

  • Open and closed comedones (blackheads and whiteheads)
  • Papules (small, tender red bumps)
  • Pustules (white or yellow “squeezable” spots)

Deeper lesions

  • Nodules (large painful red lumps)
  • Pseudocysts (cyst-like fluctuant swellings)

Secondary lesions

  • Excoriations (picked or scratched spots)
  • Erythematous macules (red marks from recently healed spots, best seen in in fair skin)
  • Pigmented macules (dark marks from old spots, mostly affecting those with dark skin)
  • Scars or various types

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).

Acne vulgaris Acne vulgaris Acne vulgaris
Acne vulgaris

More images of acne …

Acne grading

Acne may be classified as mild, moderate or severe1. Comedones and inflammatory lesions are usually considered separately.

Mild acne

  • <20 comedones
  • <15 inflammatory lesions
  • Or, total lesion count <30

Moderate acne

  • 20–100 comedones
  • 15–50 inflammatory lesions
  • Or, total lesion count 30–125

Severe acne

  • >5 pseudocysts
  • Total comedo count >100
  • Total inflammatory count >50
  • Or total lesion count >125
Classification of acne
Mild acne vulgaris
Mild acne		 Acne vulgaris
Moderate acne		 Acne vulgaris
Severe acne

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 example2,3.

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.

What is the treatment for acne vulgaris?

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.