The exact cause of seborrheic dermatitis is not fully understood, but it seems to involve an overreaction of the skin to a common yeast on the skin, along with genetic factors, hormones, and the skin’s oil production. Stress, cold dry weather, harsh skin products, and some illnesses can trigger or worsen flares.
You are more likely to get seborrheic dermatitis if you are an infant under 3 months or an adult over 60, have oily skin, or have conditions like HIV, Parkinson’s disease, depression, or alcohol dependence. Cold dry weather, stress, and harsh skin or hair products also increase the risk of flares.
Treatment focuses on reducing inflammation, yeast, and scaling with medicated shampoos, antifungal or anti‑inflammatory creams, and gentle cleansing. Most people need ongoing maintenance, using medicated products a few times a week and mild moisturizers to keep the skin calm and prevent flares.