seborrhoeic

Seborrhoeic is an adjective derived from seborrhoea, describing conditions related to the sebaceous glands or to excess sebum production. In medical usage, the term most often appears in connection with two conditions: seborrhoeic dermatitis and seborrhoeic keratosis.

Seborrhoeic dermatitis is a common inflammatory skin condition that affects areas rich in sebaceous glands, such as the scalp, eyebrows, sides of the nose, and behind the ears. It typically presents as red, flaky, sometimes greasy patches that may itch. The exact cause is not fully understood, but yeasts of the genus Malassezia, along with immune and environmental factors, are thought to contribute. Risk factors include age (peaks in adulthood), scalp oiliness, hormonal changes, and certain medical conditions that affect immunity. Diagnosis is usually clinical. Treatment focuses on controlling symptoms and may include medicated shampoos containing zinc pyrithione, selenium sulfide, or ketoconazole, as well as topical antifungals, mild corticosteroids for short-term relief, and regular skincare or scalp hygiene. In chronic or severe cases, calcineurin inhibitors or phototherapy may be used.

Seborrhoeic keratosis is a common, benign skin term that describes waxy, “stuck-on” appearing lesions, most often on the trunk and face of older adults. The condition is not related to sebum production or sebaceous gland activity, and it is typically asymptomatic. Treatments, if desired for cosmetic reasons or irritation, include cryotherapy, curettage, electrocautery, or surgical removal.

Etymology traces to Greek for sebum flow; the term may be spelled with or without the second “o” (seborrhoeic vs. seborrhoeic).