Cosmeceuticals and Contact Dermatitis

Introduction

The term cosmetics has a broad definition and includes hair care products, skin care products, nail care products, personal care products, as well as sunscreens. The definition, however, varies between the US and Europe. Cosmetics are defined by the Food, Drug and Cosmetic Act as ‘articles intended to be rubbed, poured, sprinkled or sprayed or introduced into or otherwise applied to the human body or any part thereof for cleansing, beautifying, promoting attractiveness, or altering the appearance’ and should not alter the structure or function of the skin. Drugs are defined as ‘articles intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease in man’. Cosmeceuticals are cosmetic products that contain bioactive ingredients with the intent to have a beneficial physiologic effect although there is no legal definition. In Europe, the Cosmetic Directive 76/768/EEC defines a cosmetic product as any substance or preparation ‘intended to be placed in contact with various external parts of the body or with the teeth and mucous membranes of the oral cavity with a view exclusively or mainly to cleaning them, perfuming them, changing their appearance, and/or correcting body odors and/or protecting them or keeping them in good condition.’ Thus, some products considered cosmetics in Europe (i.e. antiperspirants) are considered over-the-counter (OTC) drugs in the US.

Cosmetics are used by many and are an integral part of daily grooming. On average, women use approximately 12 personal care products containing over 180 ingredients per day while men use an average of six personal products containing 85 ingredients. Unfortunately, sometimes these cosmeceutical products intended to enhance beauty can lead to a dermatitis that can be quite unsightly, uncomfortable, annoying and perplexing to the patient and the physician. Contact dermatitis is one of these adverse reactions and can be either irritant or allergic in nature, with the former being more common. Allergic contact dermatitis to cosmetics, personal care products, makeup, body washes, moisturizers, creams, nail, lip and hair care products, and the devices (i.e. sponges, applicators) used to apply them can result in a clinical dermatitis. These reports are well documented in the literature and clinically can appear as a well-demarcated reaction at the location of product application. However, the dermatitis can be ectopic to the location the product is applied through transfer to a more sensitive area such as the face or eyelids. Reports of allergic contact dermatitis to cosmeceuticals are not as frequently reported in the literature as one would expect given their widespread usage. This may be due in part to difficulty in testing these products and the lack of standardized allergens.

Vitamins

Contact dermatitis to cosmeceutical vitamins such as vitamin A (retinol), vitamin C (ascorbic acid), vitamin E (tocopherol), and vitamin K has been reported in the literature. Vitamin A and its derivatives, such as retinol, retinaldehyde, and retinyl palmitate, typically produce an irritant contact dermatitis with dryness and skin irritation. This irritation is an unwanted side effect of retinization of the face, but cannot be avoided if the beneficial collagen regenerative effects are to be experienced. Irritant contact dermatitis can sometimes present identically to allergic contact dermatitis, but vesiculation and facial swelling are never an expected part of early retinization of the face. Allergic contact dermatitis to vitamin A is rare, but can be confirmed by positive patch testing. The vitamin A-containing cream can be patch tested ‘as is’, but many times it is impossible to determine which of the many ingredients in the preparation is the culprit. Most large cosmeceutical manufacturers can provide a sample of the vitamin A raw material they use in their formulation for individual ingredient patch testing. The person to contact at the company and the address can be obtained from the Cosmetic Industry On Call brochure published as a joint effort between the American Contact Dermatitis Society (ACDS) and the Personal Care Products Council (PCPC; formerly the Cosmetic, Toiletry, and Fragrance Association). More information can be obtained at the PCPC website at http://www.personalcarecouncil.org .

Vitamin C, also known as ascorbic acid, is another vitamin used topically to reverse signs of aging. It is difficult to formulate because it is easily oxidized to inactive products upon exposure to ultraviolet (UV) radiation or oxygen. Allergic contact dermatitis to topical vitamin C is rare, but irritation can occur due to the low pH effects of the ascorbic acid on the skin. The same discussion regarding closed patch testing and ingredient procurement for vitamin A also applies to vitamin C.

Vitamin E is a natural or synthetic component purported to have antioxidant and antiaging properties. It can be found naturally in many substances such as barley, rice, corn, rapeseed, alfalfa, wheat, eggs and meat as well as contained in many cosmetic products including deodorants, soaps and creams for moisturizing and burn/scar relief. It is part of a family of compounds called tocopherols and is a common cause of both irritant and allergic contact dermatitis. Its role as a contact allergen is well documented and often associated with vitamin A since vitamin E is thought to enhance the actions of vitamin A. Eczematous reactions, urticarial contact dermatitis, and erythema multiforme-like eruptions have all been reported with topical alpha-tocopherol use. Many of the casually reported cases of vitamin E allergy appear to be due to consumers breaking open vitamin E capsules intended for oral consumption and rubbing the oil onto wounds or scars to promote healing. While vitamin E formulated in this manner is safe for human oral consumption, it is not intended for topical application. Cosmetic grade vitamin E properly formulated in a moisturizing cream is rarely allergenic. Patch testing may be useful for making the diagnosis of contact dermatitis from alpha-tocopherol. The recommended concentration for evaluation of localized lesions is 5%–20%; however, lower concentrations such as 0.25%–1.0% may be sufficient in generalized lesions.

Vitamin K, present in green vegetables and the liver, has been used topically following cosmetic surgical procedures including liposuction, sclerotherapy, carbon dioxide and pulse dye laser procedures. Adverse cutaneous effects are rarely reported; however, dermatitis is more common with lipid soluble forms such as phytomenadione due to greater percutaneous absorption. In addition, cutaneous hypersensitivity reactions to vitamin K ₁ following subcutaneous or intramuscular injection as well as irritant contact dermatitis from vitamin K ₃ use have all been reported in the literature. Patch testing may be helpful in further assessing for contact dermatitis to vitamin K.

Hydroxy acids

Hydroxy acids are a group of chemicals frequently found in cosmeceutical products. Contact dermatitis to alpha-hydroxy acids (AHAs), beta-hydroxy acids (BHAs), and polyhydroxy acids (PHAs) is typically in the form of irritant contact dermatitis. The larger size of PHAs reduces skin penetration, which also lessens the opportunity for irritant contact dermatitis to occur. More irritant reactions are seen with the AHAs, in the form of stinging and burning due to the low pH of these cosmeceuticals that rapidly penetrate the stratum corneum to reach the nerve endings in the dermis. AHAs that have been partially neutralized produce less contact dermatitis, but also do not produce dramatic anti-aging effects. BHAs, such as salicylic acid, are oil soluble and do not penetrate the stratum corneum well. For this reason, irritant contact dermatitis is lessened, but can still occur in patients with compromised barrier function.