Seborrheic dermatitis signs and symptoms may include: 
Flaking skin (dandruff) on your scalp, hair, eyebrows, beard or mustache
Patches of greasy skin covered with flaky white or yellow scales or crust on the scalp, face, sides of the nose, eyebrows, ears, eyelids, chest, armpits, groin area or under the breasts
Rash that may look darker or lighter in people with brown or Black skin and redder in those with white skin
Ring-shaped (annular) rash, for a type called petaloid seborrheic dermatitis
Itchiness (pruritus)
 The signs and symptoms of seborrheic dermatitis tend to flare with stress, fatigue or a change of season.