What Is Seborrheic Dermatitis? Symptoms, Causes, and Treatment

Seborrheic dermatitis is a common inflammatory skin condition that causes red, scaly, and often greasy patches on areas of your body with many oil glands. It most frequently affects the scalp, causing flaking that looks like dandruff, but can also appear on your face, chest, and other areas. Studies show that seborrheic dermatitis affects about 4% of the general population, with rates reaching up to 70% in infants under 3 months old.

While seborrheic dermatitis is a chronic condition that tends to come and go, understanding what causes it and how to manage it can help you control flare-ups and reduce symptoms.

What Is Seborrheic Dermatitis?

Seborrheic dermatitis is a type of eczema that develops in areas where your skin produces more oil (sebum). Unlike other forms of eczema that cause dry, itchy skin, seborrheic dermatitis creates oily, yellowish scales along with redness and inflammation.

When seborrheic dermatitis affects only the scalp with mild symptoms and no inflammation, it's commonly called dandruff. However, when the condition becomes more severe or spreads to other parts of your body, it's classified as seborrheic dermatitis.

Common Symptoms

Seborrheic dermatitis symptoms can vary in severity but typically include:

• Red or salmon-colored patches on the skin

• White or yellowish flaky scales that may look greasy

• Itching or mild discomfort (though not always present)

• Dandruff-like flaking on the scalp

Where It Appears

The condition typically shows up in areas with more oil glands:

• Scalp (most common location)

• Sides of the nose and eyebrows

• Behind the ears

• Upper chest and back

• Skin folds (armpits, under breasts, groin)

What Causes Seborrheic Dermatitis?

The exact cause isn't fully understood, but research points to an inflammatory reaction to Malassezia, a type of yeast that naturally lives on everyone's skin. When this yeast overgrows or your skin reacts to it, inflammation and flaking occur.

Several factors may contribute to seborrheic dermatitis:

• Overactive oil glands producing excess sebum

• Changes in your immune system response

• Genetic factors (it can run in families)

• Disrupted skin barrier function

• Stress and hormonal changes

Seborrheic dermatitis is not contagious and is not caused by poor hygiene. In fact, washing too frequently or using harsh products can sometimes make symptoms worse.

How It Differs from Dandruff and Eczema

Seborrheic Dermatitis vs. Dandruff

Dandruff is actually a mild form of seborrheic dermatitis limited to the scalp. The main differences are:

• Dandruff causes white flakes without redness or inflammation

• Seborrheic dermatitis includes redness, inflammation, and can affect multiple body areas

• Seborrheic dermatitis scales tend to be yellowish and greasier

Seborrheic Dermatitis vs. Atopic Eczema

While both are types of eczema, they have different causes and characteristics:

• Seborrheic dermatitis is linked to yeast on the skin; atopic eczema involves allergies and skin sensitivity

• Seborrheic dermatitis appears in oily areas; atopic eczema can occur anywhere

• Seborrheic dermatitis creates greasy scales; atopic eczema causes dry, rough patches

Treatment Options

While there's no cure for seborrheic dermatitis, several treatments can effectively control symptoms and prevent flare-ups.

Medicated Shampoos and Creams

Antifungal treatments are the most effective approach because they target the Malassezia yeast. Ketoconazole shampoo has shown excellent results in clinical studies, with 88% of patients experiencing significant improvement when used twice weekly. When used once weekly for prevention, it reduced flare-ups by more than half compared to regular shampoo.

Other helpful ingredients include:

• Selenium sulfide

• Zinc pyrithione

• Salicylic acid (helps remove scales)

Additional Treatments

For more persistent cases, your dermatologist might recommend:

• Short-term topical steroids to reduce inflammation

• Non-steroidal anti-inflammatory creams

• Combination treatments for severe cases

Managing Flare-Ups

Seborrheic dermatitis is a chronic condition that tends to come and go. To help manage symptoms:

• Use medicated shampoos regularly, even when symptoms improve

• Wash affected areas gently without scrubbing

• Avoid harsh soaps and products with alcohol

• Manage stress, which can trigger flare-ups

• Keep affected areas clean and dry

When to See a Dermatologist

Consult a dermatologist if:

• Over-the-counter treatments don't improve your symptoms after a few weeks

• The condition is widespread or causing significant discomfort

• You develop signs of infection (increased pain, warmth, oozing, or spreading redness)

• You're not sure if what you have is seborrheic dermatitis

• The condition affects your quality of life or self-confidence

A dermatologist can provide a proper diagnosis, rule out other conditions that may look similar, and create a personalized treatment plan that works for your specific situation.