Acetyl-Mandelic Acid, an Alpha-Acetoxy Acid Compound for Treating Brittle Nails

Brittle fingernails, or nail fragility, is a common disorder affecting up to 20% of individuals.¹ Depending on age, it can affect women approximately twice as often as men.² The condition is characterized by nails that split, flake, crumble, become soft, and lose elasticity. Clinically, the brittle nail condition is described with the terms onychoschizia (nail splitting, or lamellar dystrophy) and onychorrhexis (longitudinal ridging and fissuring). Brittle nails may be idiopathic³ or due to risk factors such as advancing age,⁴ systemic disease,³ certain medications,⁵ nutritional deficiencies,⁶ and cosmetic nail practices.⁷ Brittle nails may be painful and affected individuals complain of significant cosmetic concerns and impaired ability to perform household or work-related activities.^1,8 The negative impact of brittle nails on mood and quality of life (QOL) have been well- documented^9-12 and are more significant among women.¹³

Alpha-hydroxy acids are a group of naturally-occurring organic acids that are commonly used in dermatology and include lactic acid, malic acid, tartaric acid, and citric acid.¹⁴ The most commonly used alpha-hydroxy acid is glycolic acid, which is used in cosmetic skin products, shampoos, and conditioners¹⁴ to produce smoother skin surfaces with fewer wrinkles.^15,16 Topical products formulated with alpha-hydroxy acids at concentrations of 5% to 20% are used to treat acne and melasma. Products containing alpha-hydroxy acids at concentrations of 20% to 70% are used as chemical peels for noninvasive facial rejuvenation procedures performed by dermatologists.^17,18

The beneficial action of alpha-hydroxy acids on skin is due to their ability to decrease corneocyte cohesion and cause detachment and desquamation of the stratum corneum.^14,19,20  The mechanism for this is not known with certainty. One hypothesis is that alpha-hydroxy acids cause exfoliation by reducing calcium ion concentration in the epidermis, which reduces cell adhesion.^17,21

In contrast, bonding is increased by the application of some alpha-acetoxy acids. These are formed by the addition of an acetyl group to an alpha-hydroxy acid. For example, by adding an acetyl group to mandelic acid, an alpha-hydroxy acid²² forms acetyl-mandelic acid, an alpha-acetoxy acid (Figure). Acetyl-mandelic acid promotes corneocyte cohesion, hardens the nail and stabilizes keratin filaments, and thickens the stratum corneum thickness.

This forms the rationale for the use of acetyl-mandelic acid for the treatment of brittle nails (DermaNail Nail Conditioner; Summers Laboratories, Inc, Collegeville, PA). After correcting any known causative factors, a few drops of DermaNail are applied to the base of the nails, allowing it to be absorbed where the nail grows out from the cuticle. Since it takes time for healthy nails to grow and replace the brittle nails, it will take 8 to 16 weeks to yield results. In addition to treating brittle nails, DermaNail has been used as adjunct therapy for treating lichen planus.²³

References ADDIN EN.REFLIST
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