What is Cocamidopropyl Betaine?
Cocamidopropyl betaine is a synthetic surfactant made by reacting fatty acids from coconut oil with a chemical called dimethylaminopropylamine, then further processing to yield a betaine compound. Despite the coconut origin of its starting material, the final molecule is chemically distinct from anything found in a raw coconut. It carries both positive and negative charges, which is why it is classified as amphoteric.
What does it do in the product?
In a rinse-off product, cocamidopropyl betaine lowers surface tension so oils, dirt, and sebum lift away from skin or hair. It also thickens the formula and stabilises foam, giving cleansers a richer, more uniform lather. Because it softens the harshness of stronger anionic surfactants like sodium lauryl sulfate, formulators routinely combine it with those ingredients to reduce overall irritation potential.
Where you usually find it
- Shampoos and conditioning shampoos
- Body washes and shower gels
- Facial cleansers and foaming face washes
- Baby washes and gentle cleansing products
- Hand soaps and liquid hand washes
Is Cocamidopropyl Betaine something to worry about?
For most people, cocamidopropyl betaine is well-tolerated at the concentrations used in rinse-off products. However, patch-test data reviewed by dermatology bodies has identified it as one of the more common causes of contact allergy among cosmetic surfactants, and it was named Allergen of the Year by a major North American contact dermatitis group in the early 2000s. The allergen is believed to be largely impurities formed during manufacturing — chiefly amidoamine and dimethylaminopropylamine — rather than the finished betaine molecule itself.
Who should pay attention
- People with a confirmed contact allergy to CAPB or to amidoamine should avoid it
- Those with eczema or a compromised skin barrier may be more likely to react
- Individuals following a strict coconut allergy avoidance diet — the clinical relevance to topical CAPB is unclear, so check with an allergist
- Those seeking fragrance-free or allergen-reduced products should look beyond CAPB-free labelling and check for the listed impurities
- Babies and young children: generally consider rinse-off products with gentler, well-characterised surfactants when possible
How is it regulated?
In the United States, the FDA permits cocamidopropyl betaine as a cosmetic ingredient, and the Cosmetic Ingredient Review expert panel has assessed it as safe at current use concentrations in rinse-off formulas. The EU's cosmetics regulations also permit its use without a concentration limit for rinse-off products, though EFSA and the European Commission's Scientific Committee on Consumer Safety have reviewed manufacturing-related impurities and recommended tighter purity standards for finished ingredients.
How to spot it on a label
On an ingredient list, it usually appears as 'cocamidopropyl betaine' or the abbreviation 'CAPB'; some labels use the spelling 'cocoamidopropyl betaine.' It often appears in the first half of the list because rinse-off cleansers contain it at meaningful levels, frequently alongside sodium lauryl sulfate, sodium laureth sulfate, or decyl glucoside. A label claim such as 'derived from coconut' may refer specifically to this ingredient, though the finished molecule is not the same as coconut oil.
What a cleaner swap looks like
Consumers wanting to avoid CAPB can look for cleansers built around alkyl polyglucosides — such as decyl glucoside or coco glucoside — which are considered to have a lower contact-allergy profile. Sodium cocoyl isethionate or glycine-based surfactants are other mild alternatives used in sensitive-skin formulations. InZoRAH can scan an alternative product's barcode to confirm which surfactant system it actually uses.