Alkyl glucosides (AG) are a class of surfactants increasingly used in personal care products (PCPs) because of perceived lower irritancy and allergenicity compared to other surfactants 1. Sensitisation rates are reported to be low; however, positive reactions often have a high degree of clinical relevance 2-5. This study investigates positive patch test reactions to AG and evaluates their clinical relevance. A retrospective study of cases of AG Allergic Contact Dermatitis (AG-ACD) from 1st January 2016 to 31st December 2024 was performed at the Skin Health Institute (Melbourne, Australia). Patients were patch tested to decyl glucoside (DG) 5.0% in petrolatum (pet.), lauryl glycoside (LG) 3.0% pet. and cetearyl glucoside (CG) 5.0% pet. All three were included in our Cosmetics series in 2021. Additionally, DG is also tested in the Sunscreen series. However, prior to 2021, specific AGs were only selected for testing when there was a history of possible exposure. Haptens were obtained from Chemotechnique Diagnostics (Vellinge, Sweden) and fixed to skin with AllergEAZE test chambers (SmartPractice, Canada) for 48 h. Patch test readings were performed at days (D)2 and D4 by seven consultant dermatologists according to ICDRG guidelines, who subsequently assessed the relevance of positive reactions 6. The χ2 test with Yate's continuity correction and Fisher's exact test were used to assess the difference in MOAHFLA index between those with AG-ACD and those without relevant reactions (Table S1). One thousand three hundred ninety-nine patients were patch tested with at least one glucoside (CG = 1082, DG = 1399, LG = 1134) in the study period: 51 (3.6%) patients had positive reactions, with 20 (1.4%) being relevant. The proportion of positive reactions were DG (43/1399, 3.1%); LG (23/1134, 2.0%); CG (4/1082, 0.4%). DG was the most common cause of AG-ACD (17 patients, 85.0%), followed by LG (5, 25.0%) and CG (1, 5.0%), Table 1 provides case information for patients with AG-ACD, whilst Table 2 details specific reactions to AG. Facial wash (Nil) D2−, D4+/− Shampoo (Nil) D2-, D4+/− DG: D2−, D4+ LG: D2− D4− Face Scalp Other shampoo (FMII, Hydroperoxides of limonene, Hydroperoxides of linalool) D2−, D4 Perfume (FM II, Hydroperoxides of limonene†, Hydroperoxides of linalool†, Myroxylon pereirae†) D2−, D4− Hydroperoxides of linalool: D2−, D4+ (R) Myroxylon pereirae: D2−, D4+ (R) FM II: D2−, D4+ (R) Hydroperoxides of limonene: D2−, D4+ (R) Nickel sulphate: D2+, D4+ (O) Potassium dichromate: D2+/−, D4+ (O) MI: D2+, D4++ (O) MCI: D2+, D4++ (O) 2-hydroxyethyl methacrylate: D2-, D4++ (O) Ammonium persulfate: D2+, D4+ (O) Face Eyelids FM I: D2+, D4+ (R) Nickel sulphate: D2+, D4+ (O) Cobalt chloride: D2+, D4+ (O) Benzophenone-3: D2-, D4+ (O) AD AR As Face Hands Makeup remover (Hydroperoxides of linalool†) D2−, D4- Lipstick (Hydroperoxides of linalool†) D2+/−, D4+ Face Eyelids Neck Arms Daisy – leaf and stem: D2+, D4+ (O) Dogwood flower, leaf and stem: D2+, D4+ (O) Methylbenzylidene camphor: D2+++, D4+ (O) AD AR As Face Neck Gold sodium thiosulphate: D2+, D4+ (R) Diazolidinyl urea: D2-, D4+ (U) Potassium dichromate: D2+, D4+ (U) Cobalt chloride: D2+++, D4+ (U) Nickel sulphate: D2+/−, D4+ (U) AD AR Face cleanser (Nil) NT Body wash (Nil) NT Face Neck Arms Nickel sulphate: D2−, D4+ (O) Tea lauryl sulphate: D2−, D4++ (O) AD AR As Hands Arms Rubber gloves (Carba mix) NT Hand wash (Hydroperoxides of limonene, hydroperoxides of linalool, benzoic acid, sodium benzoate) D2−, D4+ Shampoo (hydroperoxides of limonene) D2−, D4+ Carba mix: D2−, D4+ (R) Hydroperoxides of limonene: D2−, D4+ (R) Benzoic acid: D2−, D4+ (R) Sodium benzoate: D2−, D4+ (R) Arnica montana extract: D2−, D4+ (U) MCI: D2−, D4+ (U) Butyl hydroxyanisole: D2−, D4+ (U) Lauryl betaine: D2−, D4+ (O) Tea lauryl sulphate: D2+, D4++ (O) AD AR As DG: D2+, D4+ LG: D2+, D4+ CG: D2−, D4− Arms Hands Aftershave (hydroperoxides of linalool†) D2−, D4− Face wash (Orange oil, Hydroperoxides of linalool†) D2−, D4− Conditioner (hydroperoxides of linalool†) D2+/−, D4− Leather motorcycle clothes (Potassium dichromate) NT Potassium dichromate: D2−, D4+ (R) Hydroperoxides of linalool: D2+/−, D4+ (R) Orange oil: D2+, D4+ (R) DG: D2+/−, D4+ LG: D2-, D4− CG: D2−, D4− Sunscreen (MBBT, Hydroperoxides of linalool) D2−, D4− Shampoo (Hydroperoxides of limonene) D2−, D4− Hydroperoxides of linalool: D2+, D4+ (R) Hydroperoxides of limonene: D2+, D4+ (R) MBBT: D2−, D4+ (R) Disodium cocoamphodiacetate: D2−, D4+ (R) BAK: D2−, D4+ (U) Textile dye mix: D2+/−, D4+ (U) Captan: D2+/−, D4+ (U) Lauryl betaine: D2−, D4+ (U) Ethylhexyl methoxycinnamate: D2−, D4+ (U) Cetrimonium bromide: D2+, D4+ (O) AD As Shampoo (Hydroperoxides of limonene†, Hydroperoxides of linalool†) D2+/−, D4+ Hand wash (Hydroperoxides of linalool) NT DG: D2+/−, D4+ LG: D2+/−, D4+ CG: D2−, D4− Scalp Hands Tea tree oil (Tea tree oil) NT Other shampoo (Hydroperoxides of linalool) D2+/−, D4+/− Hydroperoxides of linalool: D2+, D4+ (R) Hydroperoxides of limonene: D2+, D4+ (R) Tea tree oil: D2+, D4+ (R) Iodopropynyl butyl carbamate: D2+, D4+ (U) Nickel sulphate: D2 + D4 (O) Formaldehyde: D2++, D4++ (O) Imidazolinyl urea: D2+, D4+ (O) MCI: D2+++, D4+++ (O) MI: D2+, D4+ (O) Quaternium 15: D2+/−, D4+ (O) DMDMH: D2+/−, D4+ (O) Bronopol: D2+, D4+ (O) AD AR Face Hands Eyelids Neck Arms Sorbic acid: D2-, D4+ (R) Myroxylon pereirae: D2++, D4+ (O) AR As Face Back Neck Shampoo (lauryl betaine) NT Foundation (Hydroperoxides of limonene) D2+/−, D4- Hand wash (MCI, MI) NT MI: D2+, D4+ (R) MCI: D2+, D4+ (R) Hydroperoxides of limonene: D2+, D4+ (R) Lauryl betaine: D2+, D4+ (R) AD AR As Nut allergy FM II: D2++, D4++ (R) Myroxylon pereirae: D2+, D4++ (U) Isoeugenol: D2++, D4++ (U) Shampoo (Hydroperoxides of limonene†, Hydroperoxides of linalool†, Myroxylon pereirae u†) D2−, D4+ Laundry detergent (Nil) NT DG: D2+, D4+ LG: D2+/−, D4+ (U) CG: D2−, D4− Scalp Axillae Neck Myroxylon pereirae: D2+, D4+ (R) Hydroperoxides of linalool: D2+/−, D4+ (R) Hydroperoxides of limonene: D2+/−, D4+ (R) Nickel sulphate: D2−, D4+ (U) Potassium dichromate: D2++, D4+ (U) Cobalt chloride: D2−, D4+ (U) Isoeugenol: D2−, D4+ (U) Coumarin: D2+, D4+ (U) Elidel: D2−, D4+ (U) AR As Body cream (Hydroperoxides of limonene†) D2+, D4+ Sunscreen (Nil) D2+, D4+ Face cream (Nil) D2+, D4+ Makeup (Nil) NT DG: D2+, D4+/− LG: D2+, D4+ CG: D2−, D4− Face Eyelids Chest Arms Body wash (Hydroperoxides of limonene†) D2−, D4+/− Perfume (Hydroperoxides of limonene†) D2+, D4+ Deodorant (Hydroperoxides of limonene†) D2-, D4+ Scalp cleanser (Nil) D2−, D4+/− Shampoo (Nil) D2−, D4+/− DG: D2−, D4+ LG: D2−, D4- CG: D2−, D4− Face Hands Hydroperoxides of limonene: D2−, D4+ (U) Myroxylon pereirae: D2−, D4+ (U) Sodium metabisulfite: D2−, D4++ (U) AD AR As Facial cleanser (Nil) D2-, D4− Body cream (Nil) D2, D4− DG: D2−, D4+ LG: D2−, D4+/− CG: D2−, D4+/− Face Neck Chest Hands Mascara (Potassium dichromate, Aminomethyl propanol) D2−, D4− Sunscreen (BEMT) D2−, D4− Shampoo (Cocamidopropyl betaine) D2−, D4− Potassium dichromate: D2++, D4+++ (R) Cocamidopropyl betaine: D2+, D4+ (R) Aminomethyl propanol: D2+/−, D4+ (R) BEMT D2−, D4+ (R) Cobalt chloride hexahydrate: D2−, D4+ (U) Balsam of Peru: D2+, D4+ (O) DG: D2+/−, D4+/− LG: D2+/−, D4+/− CG: D2+, D4+ Face Eyelids Neck Cocamidopropyl betaine: D2+/−, D4+ (R) Nickel sulphate: D2+, D4++ (O) Cobalt chloride hexahydrate: D2−, D4+ (O) MCI: D2+, D4++ MI: D2+, D4++ (O) Hands Chest Back Other body wash (Disodium cocoamphodiacetate) D2+, D4+ Conditioner (FM I, Myroxylon pereirae†) D2+, D4+ Shampoo (FM I, Balsam of Peru†) D2+, D4+ Myroxylon pereirae: D2−, D4+ (R) Disodium cocoamphodiacetate: D2−, D4+ (R) FM I: D2+, D4+ (R) Lauryl betaine: D2++, D4+ (U) AR As Shampoo (Nil) D2+/−, D4+/− Body wash (Hydroperoxides of linalool) D2+/−, D4+/− Face Neck Conditioner (Hydroperoxides of limonene, Hydroperoxides of linalool) D2+/−, D4+/− Other shampoo (Hydroperoxides of limonene, Hydroperoxides of linalool) D2+/−, D4+/− Hydroperoxides of limonene: D2−, D4+ (R) Hydroperoxides of linalool: D2−, D4+ (R) Fifty-one patients (3.6%) had positive patch tests to AGs, with 39.2% subsequently diagnosed with AG-ACD. This is higher than reported in a study from Leeds, UK, where 1.0% of those patch tested to five AGs including DG, LG and CG had positive reactions; and from the McGill University Health Centre Database, where 0.65% of those patch tested to DG and 0.92% to LG were positive 2, 7. However, in an American study of patients with suspected cosmetic-related dermatitis who were patch tested to DG or LG, 5.4% of patients had at least one positive 8. Data from the North American Contact Dermatitis Group Patch from 2021 to 2022 showed the proportion of positive patch tests was 2.4% for DG, 1.2% for LG and 0.5% for CG, which is quite similar to our results 9. Our study found five of the thirteen (38.5%) relevant cases tested with multiple AGs reacted to more than one, within the wide range of previously reported findings (24%–88%) 1, 2, 4, 5, 7, 8. In our 20 cases with clinical relevance, 19 (95.0%) were related to PCPs, with the exception of case 7 (dishwashing liquid). The most common exposures were shampoo (25.0%), body wash (25.0%), sunscreen (20.0%) and facial cleansers (20.0%). Many PCPs were labelled as hypoallergenic; hypoallergenic PCPs have been noted to contain AG 10. However, in 17 of our 20 cases, patients reacted to additional haptens which were also present in their own products, although these products did not always react when patch tested. Nevertheless, attributing relevance can be difficult in this situation. We have identified a high degree of polysensitisation in individuals with AG-ACD. A previous study demonstrated similar findings, with 25 of 30 patients with positive reactions to AGs being polysensitised 1. Fragrances represented the majority of relevant concomitant sensitivities in our study, especially hydroperoxides of limonene (relevant in eight cases), hydroperoxides of linalool (seven), Myroxylon pereirae (three), and fragrance mixes I and II (two each), whilst associated exposures were most commonly shampoos (nine cases), conditioners (four), perfume, sunscreen and body wash (three each). The most common sites of AG-ACD were the face (excluding scalp, lips, mouth and eyelids) (75.0%), neck (45.0%), hands (40.0%), arms (30.0%) and eyelids (25.0%). Additionally, our MOAHLFA analysis found a significantly higher proportion of facial (75.0%, 34.7%; χ2(1, N = 1399) = 12.3, p = 40 years) characteristics for individuals with alkyl glucoside (AG) allergic contact dermatitis (ACD) compared to those tested to AG without a relevant reaction from a retrospective study from 1st January 2016 to 31st December 2024. Analysis was made with χ2 test with Yate's continuity correction unless otherwise specified. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Patel et al. (2026) studied this question.