Zoe Diana Draelos
Department of Dermatology, Wake Forest University School of Medicine, Winston-Salem, and Dermatology Consulting Services, High Point,
North Carolina, U. S.A.
An important consideration in formulation technology is the target site for product application. Should a skin care product be formulated for the entire body or are there unique needs for specific body sites? As a dermatologist, I am keenly aware of the need to look at each anatomic area individually to achieve optimal product functioning. Failure to do so leads to development of a product that works everywhere and nowhere. The goal of this section of the text is to explore the uniqueness of the skin in various body locations to provide a foundation for anatomic formulation considerations.
To understand formulation needs of each body area, several basic concepts must be elucidated. First, the anatomy and physiology of the body site must be identified. For example, is the skin in the area bearing hair, sebaceous gland rich, transitional between dry and moist, marked by the presence of sweat glands, hormonally mediated, acne prone, age related, etc. The second basic consideration is a discussion of the dermatologic diseases that may afflict the given skin area. Good skin care products should supplement prescription medications when disease is present, but also maintain the health of the skin and prevent disease recurrence once resolution of the dermatologic problem has occurred. Third, the hygiene needs of the skin should be considered. Is there natural bacterial colonization of the site? Is the site a mucous membrane with little resistance to viral particle penetration? Lastly, thought should be given what constitutes skin health in the area and what skin care needs should be met to allow maintenance of this health.
Only after all of these particular formulation issues have been considered can a truly quality product begin the development process. Failure to give the necessary forethought will result in a product that is met with initial enthusiasm, due to well-constructed marketing claims, but poor long-term product performance, due to lack of efficacy. This formulation textbook begins with this chapter, since these ideas form the next logical step in product development following product conception.