Figure 1. Acne

About Acne Vulgaris

Acne vulgaris, commonly referred to as acne or pimples, is a chronic inflammatory skin disease in which hair follicles linked to oil glands in the skin become clogged with dead skin cells and oil (sebum), resulting in pimples (acne lesions), oily skin, and possible scarring.1

Acne is estimated to affect more than 50 million people in the US and about 9.4% of people worldwide.2.6 It is most common in teenagers, particularly boys, but it can start in babies and persist into adulthood.1,2,3 Acne can have a significant effect on quality of life and self-esteem, particularly because acne lesions most often appear on visible areas such as the face and neck.1

Clinical Features of Acne

Figure 1. Acne

Acne lesions are most common on the face, neck, chest, shoulders, and upper back, where there is a high density of hair follicles linked to oil glands (pilosebaceous units).1.4

Acne lesions can range from blackheads and whiteheads (sometimes called non-inflammatory lesions), to inflammatory lesions, which may be papules, pustules, or nodules.4.5 These lesion types can occur separately or together, with more severe acne showing several different types of lesion.4

Acne lesions can leave behind permanent marks and scars, even when the lesion has healed; dark spots may also be left in patients with darker skin.1.5 Acne is also associated with excessive production of oil (sebum), leading to greasy-feeling skin.5

Causes of Acne

When sebum production in the skin is increased, skin cells can clump together with sebum in the hair follicles, leading them to become blocked. This can form a non-inflammatory lesion (whitehead or blackhead). The blocked follicle may then be colonized with bacteria, which live on human skin. In turn, this can lead to inflammatory changes in the hair follicle and the development of nodules and papules (inflammatory lesions).5

Many factors are associated with acne. Hormonal changes in adolescence and during the menstrual cycle are linked to the development of acne.1 Genetic factors, stress, excessive sweating, and some medical disorders such as Cushing’s syndrome or polycystic ovarian syndrome can cause or worsen acne.1.5 Some medications, such as corticosteroids, oral contraceptives, and anti-epileptic medications, may also lead to acne.1.5 Despite popular belief, there is no evidence that diet, exercise, or lack of hygiene are linked to developing acne or making it worse.1.5

Useful Links

American Acne & Rosacea Society
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  1. Williams HC, Dellavalle RP, Garner S. Acne vulgaris. Lancet. 2012;379(9813):361-372.
  2. Tan JK, Bhate K. A global perspective on the epidemiology of acne. British Journal of Dermatology. 2015;172 Suppl 1:3-12.
  3. Serna-Tamayo C, Janniger CK, Micali G, Schwartz RA. Neonatal and infantile acne vulgaris: an update. Cutis. 2014;94(1):13-16.
  4. Titus S, Hodge J. Diagnosis and treatment of acne. American Family Physician. 2012;86(8):734-740.
  5. Ayer J, Burrows N. Acne: more than skin deep. Postgraduate Medical Journal. 2006;82(970):500-506.
  6. Zaenglein AL, Pathy AL, Schlosser BJ, et al. Guidelines of care for the management of acne vulgaris. Journal of the American Academy of Dermatology. 2016;74(5):945-973.e933.

The information presented on this website is intended for educational purposes only. Readers are encouraged to consult their healthcare providers for further information.