Seborrheic Dermatitis (SD) is a common, chronic skin condition that primarily affects the scalp, but can also impact other oily areas of the body such as the face, chest, and back. Characterized by red, inflamed skin with flaky, white or yellowish scales, seborrheic dermatitis is often itchy and uncomfortable. While it's not contagious or a sign of poor hygiene, it can be persistent and challenging to manage.