Guar hydroxypropyltrimonium chloride
The conditioning polymer that works from inside a shampoo.
How common
758 of 14,784 products with a full ingredient list in Open Beauty Facts; No. 54 of all the names found on their labels.
What it is
Cationic guar: a polysaccharide (a long sugar chain) carrying positive charges.
SourceHide
Cationic guar is an important polysaccharide used as a hair conditioning agent in personal care products.
[1] Study · 2021 · open source
Why it is in products
To condition hair from a shampoo. It is one of the standard conditioning polymers that new ones are measured against.
2 sourcesHide
Cationic guar is an important polysaccharide used as a hair conditioning agent in personal care products.
[1] Study · 2021 · open sourceCommercial conditioning polymers: Polyquaternium-10 (PQ-10) (UCARE Polymer LR-30M) and Guar Hydroxypro-pyltrimethylammonium Chloride (Jaguar C-13S) were used as performance benchmarks.
[2] Study · 2004 · open source
What it does
It sticks to hair by its charge and leaves a layer on the surface; the polymer’s size (molecular weight) largely sets how thick the layer is.
Some evidencehair2 sourcesHide
as it interacts electrostatically with hair
[1] Study · 2021 · open sourceThe MW of the cationic guar variants plays an integral role in determining the thickness of the adsorbed polymer layer on the hair surface
[1] Study · 2021 · open source
Where it works
On the hair’s surface, as a thin polymer layer.
Some evidenceSourceHide
the thickness of the adsorbed polymer layer on the hair surface[1] Study · 2021 · open source
Rules
European Union
No EU limit: it is not on the regulation’s lists of banned or restricted substances, preservatives or UV filters.
How we checkedHide
We searched Annexes II to VI of the EU regulation (consolidated text of 18 May 2026): no entry.open the list
United States
Not on the FDA’s list of prohibited or restricted cosmetic ingredients. In the US, cosmetics and their ingredients (other than colour additives) don’t need FDA approval before sale.
SourceHide
Under U.S. law, cosmetic products and ingredients, other than color additives, do not need FDA approval before they go on the market
[3] US Food and Drug Administration · open sourceWe searched the FDA’s list of prohibited and restricted cosmetic ingredients: no entry.open the list
Sources
- Investigation of the interactions of cationic guar with human hair by electrokinetic analysis McMullen RL et al., International journal of cosmetic science, 2021StudyAuthors include staff of Ashland
- Effects of low-level hydrophobic substitution on conditioning properties of cationic cellulosic polymers in shampoo systems Drovetskaya TV et al., Journal of cosmetic science, 2004StudyAuthors include staff of Amerchol (Dow)
- Prohibited & Restricted Ingredients in Cosmetics | FDA US Food and Drug Administration
Checked against these sources on 4 November 2026. Spot a mistake? Tell us.