Seborrheic Dermatitis
Seborrheic dermatitis is a common, chronic inflammatory condition affecting oil-gland-rich areas (scalp, face, chest), per the 2025 AAFP clinical review.
Symptoms
Greasy, yellowish scaling and redness on the scalp, eyebrows, sides of the nose, and chest, ranging from mild dandruff to more inflamed, itchy patches.
Causes and risk
Overgrowth of Malassezia yeast, a normal skin resident, interacts with sebum production and the skin's immune response; it's more severe and widespread in people who are immunocompromised.
How it is evaluated
Diagnosis is clinical based on the characteristic appearance and distribution.
Treatment
Topical antifungals and topical corticosteroids are both first-line with strong ("A"-level) evidence, per Cochrane review data supporting antifungals specifically. Newer options like roflumilast foam (FDA-approved for ages 9 and up) are available for those who prefer to avoid steroids.
When to seek care
Widespread, severely inflamed, or oozing lesions -- especially in someone immunocompromised -- warrant prompt evaluation for secondary infection.