Seborrheic dermatitis is a common skin condition that causes flaky,dry, white to yellowish scales to form on oily areas esp under the nose or anywhere on face
. People with seborrheic dermatitis
produce too much sebum (the natural skin oil). Later, pityrosporum yeast grows excessively in the sebum, sometime along with bacteria, making the dermatitis more persistent.
Topical antifungals and mild steroids are the usual treatment and combination of the two can be used to treat stubborn patches.