Abstracted Section from Harry’s Cosmeticology, 9th Ed.
By Charles Warren
ANTIPERSPIRANTS / DEODORANTS
The most significant difference between these two subcategories is that an A/P is an over-the-counter drug while a deodorant is purely a cosmetic product. While the formulations may be very similar in nature, the OTC drug requirements are significantly different.
Both of these product subcategories are found in similar forms. The most common forms are: stick, pressurized aerosol spray, liquid/lotion/cream, roll-on, and powder spray. These forms also come under the regulation of maximum allowable VOCs, which can vary from state to state. Prior to initiating formulation, regulatory or legal groups should be consulted regarding the applicable regulations that will impact the final formula.
Perspiration is the body’s natural mechanism for cooling. Sweat, particularly in the armpit area, pools and allows bacteria to grow (warm, moist, undisturbed area). This accumulation of bacteria leads to the characteristic negative odour associated with the sweat. Deodorants are applied to allow the body to sweat but mask the unpleasant odor.
Some deodorants contain materials to actually kill the bacteria while making the malodor. Antiperspirants contain materials that actually stop the sweat from exuding from the pores by creating small, gel-like plugs. These products also provide masking for any malodors that may develop from low levels of sweat that manage to exude. Because the function of the antiperspirant is to interfere or interact with a bodily function, it falls under the purveyance of an over-the-counter drug (OTC) and is bound by the specific monograph related to antiperspirants. The monograph indicates which active ingredients are allowed, what levels they may be used at, claims that may be made, etc. General OTC requirements govern stability testing required, manufacturing site registration, labelling requirements, etc. Again, of formulating OTC products, consultation with regulatory/legal groups is highly recommended.
The most common active ingredients found for the OTC products are aluminum zirconium tetrachlorohydrate (commonly used in sticks) and aluminum chlorohydrate (commonly used in sprays and roll-ons).