seborrheic dermatitis

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Seborrheic Dermatitis



Seborrheic dermatitis is a common inflammatory disease of the skin characterized by scaly lesions usually on the scalp, hairline, and face.


Seborrheic dermatitis appears as red, inflamed skin covered by greasy or dry scales that may be white, yellowish, or gray. It can effect the scalp, eyebrows, forehead, face, folds around the nose and ears, the chest, armpits (axilla), and groin. Dandruff and cradle cap are mild forms of seborrheic dermatitis, and appear as fine white scales without inflammation.

Causes and symptoms

The cause of seborrheic dermatitis is unclear, though it is has been linked to genetic or environmental factors. Pityrosporum ovale, a species of yeast normally found in hair follicles, has been proposed as one possible causative factor. A high fat diet and alcohol ingestion are thought to play some role. Other possible risk factors include:
  • stress and fatigue
  • weather extremes (e. g. hot, humid weather or cold, dry weather)
  • oily skin
  • infrequent shampoos
  • obesity
  • Parkinson's disease
  • AIDS
  • use of drying lotions that contain alcohol
  • other skin disorders (for example acne, rosacea, or psoriasis)
Mild forms of the disorder may be asymptomatic. Symptoms also disappear and reappear, and vary in intensity over time. When scaling is present, it may be accompanied by itching that can lead to secondary infection.


The diagnosis of seborrheic dermatitis is based on assessment of symptoms, accompanied by consideration of medical history.


Treatment consists of vigorous shampoos with preparations that assist with softening and removing the scaly accumulations. For mild cases, a nonprescription shampoo with selenium sulfide or zinc pyrithione may be used. For more severe problems, the doctor may prescribe shampoos containing coal tar or scalp creams containing cortisone. The antiseborrheic shampoo should be left on the scalp for approximately five minutes before rinsing out. Hydrocortisone cream may also be ordered for application to the affected areas on the face and body. Application of the hydrocortisone should be discontinued when the condition clears and restarted with recurrence.


This chronic condition may be characterized by long periods of inactivity. Symptoms in the acute phase can be controlled with appropriate treatment.

Key terms

Acne — A chronic inflammation of the sebaceous glands that manifests as blackheads, whiteheads, and/or pustules on the face or trunk.
Psoriasis — A skin disorder of chronic, itchy scaling most commonly at sites of repeated minor trauma (e.g. elbows, knees, and skin folds). It affects up to 2% of the population in Western countries—males and females equally.
Rosacea — A chronic inflammation of the face, with associated scattered round nodules and increased reactivity of the facial capillaries to heat. It is most common in females, aged 30-50 years.


The condition cannot be prevented. The severity and frequency of flare-ups may be minimized with frequent shampoos, thorough drying of skin folds after bathing, and wearing of loose, ventilating clothing. Foods that appear to worsen the condition should be avoided.



Monahan, Frances, and Marianne Neighbors. Medical Surgical Nursing: Foundations for Clinical Practice. Philadelphia: W. B. Saunders, 1998.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


1. affected with or of the nature of seborrhea.
2. pertaining to those areas of the body whose sebaceous glands are abundant, as the scalp, face, and axillae.
seborrheic dermatitis an inflammatory condition, usually of the skin of the scalp, with yellowish greasy scaling of the skin and itching. A mild case in the scalp is called dandruff. Seborrheic dermatitis can involve other areas such as the face, neck, central part of the trunk, or axilla. The underlying cause is not known; the hair and scalp may be excessively oily, but the connection (if any) between this and the dermatitis is not known. Although there is no specific cure for dandruff, various measures are used to control and relieve it. Most patients can control scalp scaling by frequent use of a shampoo containing zinc pyrithione, selenium sulfide, or tar. The dermatitis responds well to hydrocortisone cream.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

seb·or·rhe·ic der·ma·ti·tis

, dermatitis seborrheica
a common scaly macular eruption that occurs primarily on the face, scalp (dandruff), and other areas of increased sebaceous gland secretion, especially during infancy and after puberty; the lesions are covered with a slightly adherent oily scale. Effectiveness of treatment with betaconazole supports an etiologic role for Pityrosporum ovale infection.
Farlex Partner Medical Dictionary © Farlex 2012

seborrheic dermatitis

Cradle cap; dandruff Dermatology An idiopathic dermatopathy characterized by greasy or dry white scales, variably accompanied by erythmea Sites Scalp, face, nose, eyebrows, behind ears, external ear, skin over sternum and over skin folds Risk factors Familial, stress, fatigue, temperature extremes, oily skin, infrequent shampoos or skin cleaning, acne, obesity, excess use of lotions with alcohol, AIDS, neurologic conditions–eg, Parkinson's disease, head injury, stroke
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

seb·or·rhe·ic der·ma·ti·tis

, dermatitis seborrheica (seb'ōr-ē'ik dĕr'mă-tī'tis, seb-ōr-ē'i-kă)
A common scaly macular eruption that occurs primarily on the face, scalp (dandruff), and other areas of increased sebaceous gland secretion; the lesions are covered with a slightly adherent oily scale.
Synonym(s): dyssebacia, dyssebacea, seborrheic dermatosis, seborrhoeic dermatitis, Unna disease.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


Paul Gerson, German dermatologist and staining expert, 1850-1929.
Unna disease - Synonym(s): seborrheic dermatitis
Unna mark - a pale vascular birthmark found on the nape of the neck in 25% to 50% of normal persons. Synonym(s): nape nevus
Unna stain - an alkaline methylene blue stain for plasma cells.
Unna syndrome - Synonym(s): seborrheic dermatitis
Unna-Pappenheim stain - a contrast stain used to detect RNA and DNA in tissue sections; used to demonstrate plasma cells during chronic inflammation.
Unna-Taenzer stain - Synonym(s): Taenzer stain
Unna-Thost syndrome - uniform keratoderma of the palms and soles, usually presenting in the first six months of life.
Medical Eponyms © Farlex 2012

seb·or·rhe·ic der·ma·ti·tis

, dermatitis seborrheica (seb'ōr-ē'ik dĕr'mă-tī'tis, seb-ōr-ē'i-kă)
A common scaly macular eruption that occurs primarily on the face, scalp (dandruff), and other areas of increased sebaceous gland secretion.
Synonym(s): dyssebacia, dyssebacea, Unna disease.
Medical Dictionary for the Dental Professions © Farlex 2012