Formula Anatomy Deciphered—Feminine Hygiene Products

By: Luigi Rigano, PhD, Studio Rigano Industrial Consulting Laboratories

Posted: December 4, 2012, from the December 2012 issue of Cosmetics & Toiletries.

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Soothing: Personal hygiene cleansing formulations may be enriched with soothing and emollient substances, possibly leaving a residual perception of comfort. Vegetal extracts and their active principles are frequently used, e.g., chamomile, mallow, sage, alpha-bisabolol. Long-lasting refreshing action is also frequently sought using mint extracts and menthol derivatives.

Obtaining skin moisturization through a cleansing formula is a difficult task, but betaine (trimethylglycine) and ectoin are good osmotic protectants that support the moisturization level of the intimate epithelium.¹⁷ Skin conditioning may be also obtained by the proper use of cationic conditioners at 0.1–3%. These must be compatible with the surfactant system.

Deodorant/perfuming: An effective cleansing performance requires a consistent olfactive message, provided by the disappearance of bad odors and the development of volatile perfume notes. For the sensitivity of the vaginal area, skin compatibility and safety of the perfumes used must be ensured. Moreover, their use percentage should be low. Nevertheless, the persistency of the notes should impart confidence that a clean body odor is ensured before and during any intimate activity. Recently, nontraditional preservative/bacteriostatic molecules such as caprylyl glycol, sodium levulinate and sodium anisate are gaining success, even though they are not included in the official Annex of allowed preservatives in the European Union.

The use of probiotics is a growing innovative trend in intimate cleansers. Recently, two German firms identified probiotic cultures useful for hygiene products. They discovered that in an anti-caries product, lactic acid-producing bacteria prevents other harmful bacteria from causing tooth decay. In skin care, the same can prevent the development of odor and support the regeneration of the skin’s protective microbial flora. Reportedly, these microorganisms can also be used in lotions or creams to help keep a healthy skin equilibrium or to improve the effectiveness of deodorants, through their ability to inhibit odor-producing bacteria on the feet and armpits. These probiotic lactic acid bacteria can be used in a live or freeze-dried form.¹⁸

Personal Hygiene Deodorants

Simple cleansing may not ensure lasting deodorant efficacy in the genital region, and a personal deodorant product may be required. Together with perfumes, these formulae contain some nonaggressive bactericides. They have a similar composition and ingredients to their underarm deodorant counterparts, but the vehicle for the antibacterial agent is a dry-feel oil such as such a short-chain synthetic ester or ethers instead of alcohol. These vehicles also deliver the perfume molecules. Some carriers are butylene glycol dicaprate-dicaprylate, octyl ether or other dry oil emollients that are actuated by aerosol systems. Alcohol is not used in these systems due to its irritation potential for this sensitive area. A mild antibacterial action is provided by bacteriostatic active ingredients, selected among the least probable to induce allergic reactions. These include polyhexamethylene biguanide or chlorhexidine chlorohydrate, which is insoluble in the vehicles.