Coco-Glucoside

At a glance

Function: Non-ionic sugar-based surfactant
Origin: Semi-synthetic (glucose and coconut alcohol)
Product areas: Hair care

What it is

Coco-glucoside is not a single substance but a mixture: glucose joined to the fatty alcohols of coconut oil, whose chains run from eight to eighteen carbon atoms. Non-ionic like the other sugar surfactants. In this inventory it is the single most widespread surfactant of all — it appears in every shampoo of the salon line but one, plus in a rebuilding treatment.

Chain length is no side issue here. The irritant effect of alkyl glucosides decreases as chain length increases; this is documented as a structure-response relationship in the assessment by the US expert panel. A mixture running from C8 to C18 therefore contains both the less and the more irritating members — in what proportion appears on no ingredient list.

Assessment

Result: Increased attention
Confidence: medium
Evidence: C — limited evidence
Applies to: Cosmetics, hair care, rinse-off products, sugar-based surfactant in nearly every shampoo of a salon line

Why

Why “increased attention”: not because of its own case numbers — there are barely any — but because of the combination of prevalence and a testing gap. A 2024 study analysed the thirty best-selling products in each of four categories at a large online retailer. Alkyl glucosides appeared in 56.7 per cent of shampoos marketed as hypoallergenic, and the most frequently present was not decyl or lauryl glucoside but coco-glucoside. The authors conclude that the substance belongs in the standard patch test series.
That is exactly where it is not. Decyl glucoside is the one routinely tested, with lauryl glucoside added in some series. Someone reacting to coco-glucoside who is tested only with the other two may receive a negative result and carry on using the product. The same gap is described in the record on Lauryl Glucoside; here it is wider, because this substance occurs more often.
The safety assessment itself is unremarkable and was checked in the original for this classification. Coco-glucoside is one of the nineteen alkyl glucosides assessed; in a use test on 213 people at one per cent it was neither irritating nor sensitising, and slightly irritating in a patch test at two per cent. The assessment applies with the same proviso as for the whole group: the formulation must not be irritating.
The real question is concomitant reactions, and the answer is divided. A British analysis at two centres tested five alkyl glucosides together, including coco- and cetearyl glucoside: of 2,796 people so tested, 29 reacted to at least one, just over one per cent. The paper's title is also its finding — concomitant reactions between the glucosides are common but not ubiquitous.
How far “common” reaches is itself disputed: in one clinic series 65 per cent of glucoside-allergic patients reacted to decyl and lauryl glucoside together; in the North American test cycle of 2017/2018 it was 32.1 per cent, while 41.8 per cent reacted to decyl alone and 26.1 per cent to lauryl alone. These do not contradict each other, they are different surveys — but the conclusion runs both ways: a negative result on one glucoside does not exclude the others, and a positive one does not condemn them all.

When the assessment differs

Use level: industry surveys report up to fifteen per cent for rinse-off products and 0.2 to 8 per cent for non-colouring hair products. The range is wide, and an ingredient list does not reveal where a given product sits within it.
Occupational repetition: for the salon the question is not the single wash but the daily one. The substance is in nearly every shampoo of this line — that is an accumulation on one person, not a spread across many products.
Products that stay on the skin: contact time there is incomparably longer; for coco-glucoside this is the smaller share of reported uses.
Children: the substance is also reported in baby products; no use concentrations are available for these.
Known glucoside allergy: this substance must then be explicitly considered, even if the test with another glucoside came back negative.

Open questions

Concentration in the actual products: not available.
The 2024 study was evaluated only through its freely accessible summary; the full text was not available. That is the reason for evidence level C.
No dedicated frequency figure for coco-glucoside in patch test series is available — precisely because the substance is usually not included there.
How the 29 reactions in the British analysis are distributed across the five glucosides tested does not emerge from the available summary.
The chain-length distribution of the raw material used is not known; it determines the irritant effect.

Sources for this assessment

Applies to: Surfactants

Cetearyl Glucoside — Emulsifier (sugar-based surfactant)
Cocamide MEA — Foam booster and thickener
Cocamidopropyl Betaine — Mild surfactant, cleansing
Coco-Betaine — Amphoteric surfactant

Further substances from the same group for which a long-form assessment already exists.

Recorded in the following products

This list documents the products in which the ingredient was declared at the time of recording. It is not a statement about those products and not a recommendation. Manufacturers change formulations; the ingredient list on the current packaging is always authoritative.

All shampoos except Keep Curl
Power Build Revamp

Sources documenting its occurrence

Manual OCS Salon Manual Care 2026 Professional manual supplied for this project