Seborrheic dermatitis - Hair and ScalpSee also in: Overview,Anogenital
Alerts and Notices
SynopsisSeborrheic dermatitis is a common inflammatory papulosquamous condition that affects the sebum-rich areas of the body, including the face, scalp, neck, upper chest, and back. The pathogenesis is not known with certainty, but it may be related to an abnormal immune response to Pityrosporum (Malassezia) yeast, a common skin commensal.
Seborrheic dermatitis presents in infants as a self-limited eruption caused by persistent maternal androgens, or in adults, after adrenarche. Up to 5% of adults are affected by seborrheic dermatitis, and the condition is particularly common after the fifth or sixth decades.
Clinical presentations of seborrheic dermatitis are widely varied, ranging from simple "dandruff" to fulminant rash. There is often dryness, pruritus, erythema, and fine, greasy scaling in characteristic sites, such as the scalp, eyebrows, glabella, nasolabial folds, the beard area, upper chest, external ear canal, posterior ears, eyelid margins (blepharitis), and intertriginous areas. Anogenital involvement has also been reported. One or multiple sites may be involved. In persons with darker skin phototypes, the involved areas may be hypopigmented or hyperpigmented. These pigmentary changes may persist after treatment.
Stress may exacerbate the condition. In immunocompromised persons and those with neurologic conditions, such as Parkinson disease or stroke, seborrheic dermatitis may be severe and recalcitrant.
Since seborrheic dermatitis is such a common disorder, it has been difficult to associate it with specific medications. However, there are some published associations of medications causing, triggering, or exacerbating the condition (see Drug Reaction Data table).
Even with treatment, seborrheic dermatitis tends to be a chronic condition, and remissions and exacerbations are expected. Seborrheic dermatitis is often better in summer months and worse in the winter.
Immunocompromised patient considerations:
- Seborrheic dermatitis is more common and more severe in persons infected with the human immunodeficiency virus (HIV). It may regress with highly active antiretroviral therapy, but remissions and exacerbations can be expected.
- Seborrheic dermatitis is also often seen in patients with Parkinson disease. The course is chronic and relapsing and may be difficult to treat.
- Associated Pityrosporum folliculitis may be seen in immunocompromised patients.
L21.9 – Seborrheic dermatitis, unspecified
50563003 – Seborrheic dermatitis
Differential Diagnosis & Pitfalls
- Chronic atopic dermatitis patients are often aware of their atopic history, which commonly starts in childhood. More pruritic than psoriasis. The scalp may be involved with pruritic pink plaques with thinner scale, erosions, and excoriations.
- Psoriasis – Silvery scales sit atop well-demarcated plaques. Seborrheic dermatitis and psoriasis frequently overlap.
- Tinea capitis – Scale at leading edge of erythema with central clearing. Broken-off hairs or inflammatory boggy plaques (kerion) may be seen. Perform a KOH (potassium hydroxide) preparation of scales and hair.
- Contact dermatitis – The scalp is initially spared in a contact dermatitis to a contactant that has been applied to the scalp, such as a shampoo. Initially, this will manifest on the skin around the scalp, and only after repeated exposure will the scalp be affected.
- Dermatomyositis – Scalp involvement manifests with very pruritic and scaly violaceous erythema.
- Pityriasis amiantacea – Thick adherent scales surround proximal hair shafts. It may be an isolated finding or it may occur in association with inflammatory conditions. Of these, psoriasis and seborrheic dermatitis are most commonly seen.
- Secondary syphilis – "Moth-eaten" alopecia without scales is seen. Check rapid plasma reagin (RPR) and evaluate for history of primary chancre and systemic symptoms.
- Crusted scabies – Most often seen in elderly, immunocompromised, or institutionalized patients. Scalp is typically spared; however, there are anecdotal cases of scalp involvement in immunocompromised individuals.
Drug Reaction DataBelow is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.
Patient Information for Seborrheic dermatitis - Hair and Scalp
OverviewSeborrheic dermatitis, also known as seborrhea, is a common noncontagious condition of skin areas rich in oil glands (the face, scalp, and upper trunk). Seborrheic dermatitis causes overproduction and flaking of skin cells and sometimes itchy skin. It can vary in severity from mild dandruff of the scalp to scaly patches on the skin. Normal skin yeast called Pityrosporum ovale lives in oil-rich skin regions and plays a role in this disorder; the changes seen in the skin are due to the body's inflammatory response to the yeast on the skin. Seborrheic dermatitis seems to worsen with stress, dry weather, and infrequent shampooing. Although there is no cure for seborrheic dermatitis, control is usually possible with medicated shampoos and topical steroids (when inflammation is prominent).
Who’s At RiskDandruff occurs in 15%-20% of the population, and more severe seborrheic dermatitis (with flaking and inflamed skin) occurs in 3%-5% of all people. Seborrheic dermatitis affects all races / ethnicities and may be a bit worse in men. It typically starts after puberty (although babies may have a variant called cradle cap). The severity of seborrheic dermatitis peaks around age 40 and then may improve. Severe seborrheic dermatitis is frequently seen in people with Parkinson disease, central nervous system problems, and HIV infection.
Signs & Symptoms
- The scalp is itchy and sheds white, oily skin flakes.
- One or more of the following areas has patches of scaly skin: the scalp, hairline, forehead, eyebrows, in between the eyebrows, the area of the eyelid between the eye and the eye lashes (the free lid margin), creases of the nose and ears, ear canals, beard area, breastbone, midback, groin, and underarms. In lighter skin colors, affected areas may appear pink or red; in darker skin colors, the redness may be subtle, or affected areas may appear purplish or darker brown, but the affected areas may also look lighter in color (hypopigmented).
- Mild – only some flaking and skin color change (as outlined above) in a few small areas.
- Moderate – several areas affected with bothersome skin color change and itch.
- Severe – large areas of skin color change and severe itch that do not improve with self-care measures.
Self-Care GuidelinesMost cases of seborrheic dermatitis are easy to control with nonprescription home treatments. These include:
- Frequent shampooing or a longer lather time with shampoo. If a regular daily shampoo fails, consider an over-the-counter dandruff shampoo. There are several types on the market, and one may work better for one individual than another.
- Shampoos containing ketoconazole (Nizoral), selenium sulfide (Selsun Blue), 2% pyrithione zinc (Head & Shoulders), salicylic acid (Neutrogena T/Sal), or tar-based (Neutrogena T/Gel) compounds may be helpful. Consider occasionally rotating shampoos because the ability of how well a product works (its efficacy) can change with time.
- If the scalp is covered with widespread, dense scale, the scale may first be removed by applying warm mineral oil or olive oil to the scalp and washing several hours later with a detergent, such as a dishwashing liquid or a tar shampoo.
- Some over-the-counter creams will help if the medicated shampoo is not working well enough. These can be added to the shampoo until there is improvement and then can be discontinued; these creams can be used again temporarily as needed and include:
- Creams that reduce the Pityrosporum yeast (clotrimazole [Lotrimin], miconazole [Monistat]).
- Hydrocortisone cream (eg, Cortaid), which may work well at first but may be less helpful if used for a long time.
- Managing eyelid inflammation (called blepharitis) by gentle cleaning of the skin around the eyelashes (eyelid margins) with a cotton swab and baby shampoo (eg, Johnson's Baby Shampoo).
When to Seek Medical CareSeek medical help from a dermatologist or other medical professional if there is no response to self-care measures.
- Corticosteroid creams, lotions, or solutions
- Sulfur or sulfacetamide products, such as a wash, cream, or lotion, applied on the skin (topically)
- Prescription-strength ketoconazole shampoo or cream
- Tacrolimus (Protopic) ointment or pimecrolimus (Elidel) cream
Seborrheic dermatitis - Hair and ScalpSee also in: Overview,Anogenital