Cetyl, Cetearyl and Stearyl Alcohol, Explained: Why These Waxy Fatty Alcohols Are Not Drying Alcohol, What the CIR Concluded, and Where Rare Reactions Come From

What the ingredient is

Cetyl alcohol has 16 carbons and stearyl alcohol has 18. Cetearyl alcohol is a mixture, which the CIR's 1988 report describes as roughly 65 to 80 percent stearyl and 20 to 35 percent cetyl.

What it does in a formula

The CIR lists their roles in lotions as emollient, emulsion stabilizer, viscosity control agent, coupling agent and foam stabilizer. They thicken a cream and keep oil and water mixed; they are not actives. See where an emollient fits in our moisturizer guide.

Not the same as alcohol denat

Alcohol denat is denatured ethanol, a small volatile solvent. Our alcohol denat guide explains it. On a label, names starting with cetyl, stearyl, cetearyl or behenyl belong to the waxy family.

What the CIR concluded

The panel's final report on cetearyl, cetyl, isostearyl, myristyl and behenyl alcohols appeared in the Journal of the American College of Toxicology in 1988. It concluded they are safe as cosmetic ingredients in the present practices of use. Check the CIR's site for newer reviews.

What the human studies measured

Irritation and sensitization studies of formulations containing up to 8.4 percent cetyl alcohol showed no substantial evidence of either. In a human sensitization study of a cream with 3.0 percent cetearyl alcohol, no subject had a positive reaction.

Where reactions come from

In one clinic series cited by the CIR, 330 patients with eczema or leg ulcers were patch tested with 30 percent cetyl alcohol in petrolatum, and 11.2 percent reacted. Other studies found 2 positives among 1,664 patients and none among 100. The authors of the larger series linked their high figure to patients often being treated with a cetyl alcohol cream. That strength is far above a moisturizer, and the skin was already damaged. See irritant vs allergic dermatitis. Wool alcohols are a separate allergen, covered in our lanolin guide.

Pores and what the data cannot say

The CIR reported minimal irritation and no sensitization or comedogenicity for C16 and C18 alcohols in rabbits. That is animal data and says little about a whole cream on your face.

The short version

Fatty alcohols are texture and emulsion ingredients, not drying alcohols. Documented reactions come mostly from high-strength clinic patch tests on affected skin. Patch-test any new product on a small area first, and see a dermatologist for a persistent rash or reaction you cannot explain. This article is general information and not medical advice.