Contact Allergy to Alkyl Glucosides: A Review-Part 1.

This is Part 1 of a 2-part narrative review of contact allergy and allergic contact dermatitis (ACD) to alkyl glucosides. It discusses the nature of alkyl glucosides (mainly decyl, lauryl, cetearyl, and coco-glucoside), their properties and applications, results of patch testing in routine testing and in groups of selected patients, and presents all reported case series and case reports of ACD to decyl and lauryl glucoside. The alkyl glucosides are nonionic surfactants that are produced by the reaction of glucose with fatty alcohols and that are increasingly being used in cosmetics. This class of surfactants and emulsifiers has a low potential for irritation and favorable ecological characteristics, being manufactured from renewable sources and being completely biodegradable. Alkyl glucosides are chemically stable and hardly protein-reactive; they do not contain chemically reactive sites or strongly polarized structures. Therefore, they were not predicted to have allergenic potential. Yet, they can induce contact sensitization, which is increasingly recognized. Currently, decyl glucoside has a rate of 2.4% positive reactions in routine testing in the United States. Most positive patch test reactions have current relevance, in >80% from their presence in personal care products. Part 2 will discuss patient demographics (gender and age, atopic diathesis, distribution of dermatitis, occupational contact dermatitis), products causing ACD, patch test considerations, co-/cross-reactions between alkyl glucosides and nonrelated haptens, and the presence of alkyl glucosides in cosmetics and other products.