The Food, Drug and Cosmetics Act (FD&C Act) defines a cosmetic by its intended use, meaning cleansing, beautifying, promoting attractiveness or altering appearance. Products in this category include lipstick, perfumes, skin moisturizers, nail polish, shampoos, deodorants and any other beautifying product. [FD&C Act, sec. 201(i)].
The US Food and Drug Administration (FDA) does not consider the term cosmeceutical to be a valid product class. It is a term coined by the cosmetics industry applied to products that are said to bridge the gap between cosmetics and drugs. The term cosmeceutical often is used in cosmetic advertising and may be misleading to the consumer. If the consumer interprets the product as being similar to a pharmaceutical, he or she may conclude that cosmeceuticals are required to undergo the same efficacy and quality control testing as is required for a medication.
Drugs are either over-the-counter (OTC) or prescription (Rx) and are regulated by the FD&C Act as "articles intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease," and "articles (other than food) intended to affect the structure or any function of the body of man or other animals" [FD&C Act, sec. 201(g)(1)]. Everyday prescription drugs are referred to as legend drugs, which are separated from controlled substances by the FDA.
Since a deodorant only masks odor and an antiperspirant actually stops perspiration, i.e., affects function, a deodorant is a cosmetic and an antiperspirant is a drug. The same argument can be made for dandruff shampoo, toothpaste with fluoride, and any product with a sun protection factor (SPF). Prescription strength skin care products are only available through a physician.
To provide some clarification, shampoo is a cosmetic, but dandruff shampoo is an OTC drug; toothpaste is a cosmetic, but toothpaste with fluoride is an OTC drug; and makeup is a cosmetic, but makeup with an SPF claim is an OTC drug.