Dermocosmetic aspects of hair and scalp.

Hair cosmetic agents are preparations intended for placing in contact with the hair and scalp, with the purpose of cleansing, promoting attractiveness, altering appearance, and/or protecting them in order to maintain them in good condition. Current shampoo formulations and styling products are tailored to the variations associated with age, gender, hair quality, hair care habit, and specific problems relating to the superficial condition of the scalp. The great amount of variables to be accounted for, some of them contradictory and hard to bring into accord, makes adequate product formulation a challenge and requires continuous research. Recent hair cosmetic developments include topical hair growth stimulants, photoprotectors, and anti-aging compounds. The advances in molecular technology have opened the avenue to the study of the molecular basis of hair growth and its deviations, as well as of the aging process. The discovery of potential pharmacological targets and the development of selective and effective delivery systems following topical application indicate further strategies for maintenance of healthy hair and scalp in the young and old.