The Warning Letters appearing below illustrate an important legal distinction, the difference between a cosmetic and a drug under the Federal Food, Drug, and Cosmetic Act (FD&C Act).

Under the FD&C Act, a product intended to diagnose, mitigate, treat, or prevent disease, or to affect the structure or function of the body is classified as a drug (FD&C Act, Section 201(g)). If such a product is not generally recognized by qualified experts as safe and effective when used as labeled, it is a "new drug" (FD&C Act, Section 201(p)) and requires an approved New Drug Application to be marketed legally in the United States (FD&C Act, Section 505(a)). FDA issued Warning Letters to the following firms, citing drug claims associated with topical skin care, hair care, and eyelash/eyebrow preparations, noted on both product labeling and Web sites. Some examples of the drug claims cited are acne treatment, cellulite reduction, stretch mark reduction, wrinkle removal, dandruff treatment, hair restoration, and eyelash growth.