Encyclopedia · surfactant
Coco-glucoside
A coconut-derived mild cleanser that is a staple of sulfate-free shampoos, with the same contact-allergy caveat as decyl glucoside.
What it is
Coco-glucoside is a mixture of alkyl glucosides with mostly 8- to 16-carbon chains from coconut fatty alcohols. It is used as a mild primary or secondary surfactant and a foam booster.
How it works
It forms non-ionic micelles that are mild to the skin barrier, and as a class non-ionics extract less lipid than anionics (Thompson 2023).
What the studies show
- In a 19-year patch-test cohort of 11,842 people, 30 reacted to alkyl glucosides, with shampoos and skin cleansers (12 each) the commonest causal products (Gijbels 2014).
- A review found allergic contact dermatitis to alkyl glucosides has accumulated since the early 2000s, with cross-reactions common but not automatic (Alfalah 2017).
- A 2026 review names coco-glucoside among the main alkyl glucosides that can cause contact sensitisation despite low irritation potential (de Groot 2026).
These data concern allergy, not cleaning or hair outcomes. We found no hair-specific human trial for this ingredient, so the direct evidence is weak.
Side effects and safety
See decyl glucoside: contact allergy is rare but rising.
Bottom line
Fine for most people, particularly as part of a blend in a sulfate-free formula. Skip it if you have a known glucoside allergy.
Studies 4
Gijbels D et al. Allergic contact dermatitis caused by alkyl glucosides. 2014
Result: Causal products were shampoos (12), skin cleansers (12), sunscreens (5) and skin-care products (4); 16 patients had multiple contact allergies.
Read the study ↗Alfalah M et al. Alkyl Glucosides. 2017
Result: Alkyl glucosides were assumed low in irritancy and allergenicity, but cases of allergic contact dermatitis have accumulated since the early 2000s; sensitisation to decyl glucoside is rising in North American data; cross-reactions are common but not automatic.
Read the study ↗de Groot AC. Contact Allergy to Alkyl Glucosides: A Review-Part 1. 2026
Result: Alkyl glucosides (mainly decyl, lauryl, cetearyl and coco-glucoside) have low irritation potential but can induce contact sensitisation.
Read the study ↗Thompson CJ, Ainger N, Starck P, Mykhaylyk OO, Ryan AJ. Shampoo Science: A Review of the Physiochemical Processes behind the Function of a Shampoo. Macromol Chem Phys. 2023
Result: Reviews how surfactants lift soil from hair (roll-up, emulsification, solubilization), why shampoos pair a primary anionic with an amphoteric co-surfactant, and states that foaming does not affect cleaning. Two authors were from Unilever R&D.
Read the study ↗Related
- Decyl glucosideA plant-derived mild cleanser marketed as ultra-gentle, but its best-documented concern is a rising rate of contact allergy.
- Lauryl glucosideA 12-carbon alkyl glucoside that foams a little better than decyl glucoside and carries the same class contact-allergy profile.
- Sodium cocoyl glutamateAn amino-acid-based cleanser that was among the best-tolerated surfactants in a 105-patient patch-test study, with no scalp or hair trials yet.