My daughter has a skin reaction only on her face to buttermilk-based products. it shows up in the exact pattern as where the product is on her face..?

Irritant Dermatitis: Irritant contact dermatitis (icd) is inflammation of the skin typically manifested by erythema, mild edema, and scaling. Irritant contact dermatitis is a nonspecific response of the skin to direct chemical damage that releases mediators of inflammation predominately from epidermal cells. Treatment is with otc hydrocortisone. If this does not help see a dermatologist.