1, containing powder particles of lotion, such as furnace glycerine lotion, such lotion contains insoluble mineral powder, these mineral particles can block the sebaceous gland duct mouth, so that the discharge of sebaceous gland secretions blocked, so it is easy to induce seborrhea and folliculitis. The tincture of alcohol as a solvent, such as dermatologic tincture, the epidermis of the human facial skin is very thin, the tincture used in the face is likely to cause capillary dilation in the facial dermis, aggravating the inflammatory reaction of the skin. In addition, the face after the application of tinctures, there will be gray-black pigmentation spots. 3, containing photosensitive substances for external use, to be used with caution, such as menthol, camphor, ice chips, benzocaine, etc., will lead to allergic reactions. 4.Fluorinated strong corticosteroid creams, to be used with caution, are prone to skin atrophy, hirsutism, skin capillary dilation and other side effects. 5, topical drugs containing staining agents (such as potassium permanganate solution, Revnor solution) and corrosive agents (such as salicylic acid fire cotton paste, carbolic acid solution, trichloroacetic acid solution, etc.), can not be used for the treatment of facial skin diseases, prone to skin damage.