Dandruff and Seborrheic Dermatitis: Flaky Scalp, Causes and When to Be Seen

What it involves

MedlinePlus explains that seborrheic dermatitis is a common inflammatory skin condition that causes flaky white to yellowish scales on oily areas such as the scalp, face, or inside the ear. Dandruff is the mild form on the scalp, and cradle cap is the name used when it affects an infant's scalp.

Who this is for

• Patients with a flaky, itchy scalp that has not cleared with a regular shampoo
• Patients with greasy scaling or redness on the eyebrows, nose creases, or behind the ears
• Parents of an infant with thick yellow scales on the scalp
• Patients who are unsure whether a scaly patch is dandruff, eczema, or psoriasis

What to expect

• Questions about where the flaking is, how long it has been present, and what products you have used
• An exam of the scalp and skin, since MedlinePlus says the diagnosis is based on appearance and location
• Advice on medicated shampoos and how to use them, and when a prescription product may be needed
• Attention to other causes of a scaly rash if the pattern does not fit

Where it shows up

MedlinePlus says seborrheic dermatitis tends to form where skin is oily, and lists the scalp, eyebrows, eyelids, creases of the nose, lips, behind the ears, the outer ear, and the middle of the chest. The scales can be white and flaking or yellowish, oily, and sticky. Itching is common and may increase if the skin becomes infected, and some people have only mild redness.

What is behind it

The exact cause is unknown, according to MedlinePlus, and it may be a combination of oil gland activity, a yeast called Malassezia that lives on the skin, changes in the skin barrier, and genes. Risk factors it lists include stress or fatigue, weather extremes, oily skin or acne, heavy alcohol use, obesity, certain nervous system disorders, and HIV or AIDS. It is a skin condition and not a sign of poor hygiene.

Shampoos and creams that help

MedlinePlus says flaking and dryness can be treated with over-the-counter dandruff or medicated shampoos, and advises looking for a label that says it treats seborrheic dermatitis or dandruff. It names ingredients such as salicylic acid, coal tar, zinc, resorcinol, ketoconazole, and selenium sulfide, and says to follow the label. For severe cases, a provider may prescribe a stronger shampoo, cream, ointment, or lotion.

It comes and goes

MedlinePlus calls seborrheic dermatitis a chronic, life-long condition that comes and goes but can be controlled with treatment. Sunlight may improve it, and some people find it clears in summer. Controlling risk factors and paying careful attention to skin care can lessen how severe it gets. Hair thinning is not part of the picture, and the hair loss guide explains what causes it.

Cradle cap in infants

MedlinePlus describes cradle cap as the infant form, which usually lasts a few months and goes away by itself. Washing the baby's hair with a mild shampoo and gently rubbing the scalp with the fingers or a soft brush can help. It can also affect the eyelids, armpits, groin, and ears. Contact the child's provider if it is severe or spreading, and a prescription shampoo or cream may be advised.

Conditions that look similar

MedlinePlus lists scalp ringworm, a fungal infection that causes itchy red patches and sometimes bald spots, and scalp psoriasis, which causes thick red skin with silvery scales, as other scalp problems. The ringworm guide and the psoriasis guide describe them. Contact a provider if the patches drain fluid or pus, form crusts, or become very red or painful, which MedlinePlus lists as signs to be seen.

Sources

• MedlinePlus — Seborrheic dermatitis
• MedlinePlus — Dandruff, Cradle Cap, and Other Scalp Conditions