Cosmetic ingredients and sensitive skin: what the label can tell you

Sensitive skin and allergy are not the same

Sensitive skin has an expert definition. A special interest group of the International Forum for the Study of Itch described it as a syndrome of unpleasant sensations, such as stinging, burning, pain, itching and tingling, in response to stimuli that should not normally provoke them, and not explained by any skin disease. The skin can look normal or red, and the face is affected most.¹

Allergy works differently. An allergic reaction is the immune system overreacting to a substance, and with cosmetics it most often appears as an itchy red rash, known as allergic contact dermatitis.² Contact allergy lasts for life, and once someone is sensitised, a much lower concentration of the substance is enough to trigger symptoms. That is why EU labels name certain allergens individually: so that people who already react to one can avoid it.³

A label helps with either in the same limited way. It names what is in the product, so you can find the names you already know affect you. It cannot say how much is present, or how your skin will respond.

Fragrance, named allergens and plant oils

The FDA groups the common allergens in cosmetics into five classes: natural rubber, fragrances, preservatives, dyes and metals.² On a label a scent mixture is a single entry, Parfum in the EU or Fragrance in the US.⁴⁵ EU labels must also name the fragrance substances listed for this in Annex III, such as Linalool (entry 84) and Limonene (entry 88), once they pass 0.001% in a leave-on or 0.01% in a rinse-off product.⁶ The EU estimates that 1-9% of its population is allergic to fragrance allergens.³

Plant oils count too. The FDA says there is no regulatory definition of essential oils⁷, and since 2023 the EU has named several plant oils as allergens in their own right, such as Citrus Limon Peel Oil and the lavender oils labelled Lavandula Oil/Extract.³ So a product can carry scent without the word Parfum. On a US label, a scent's components can stay unnamed under Fragrance⁷, so a US list that names no fragrance substances does not show they are absent. Fragrance free vs unscented and EU fragrance allergen labels go into both in detail.

Preservatives with official sensitisation notes

Preservatives are another of the FDA's five classes. Its list names methylisothiazolinone, methylchloroisothiazolinone, and formaldehyde with the ingredients that release it, among them Diazolidinyl Urea, DMDM Hydantoin, Imidazolidinyl Urea and Quaternium-15.² EU law has acted on both groups:

• Methylisothiazolinone. The EU banned it from leave-on products from February 2017, citing an opinion of its Scientific Committee on Consumer Safety (SCCS) and the increased incidence of allergies it induced.⁸ A 2017 amendment then cut its limit in rinse-off products from 0.01% to 0.0015%, for the same reason.⁹ It is now permitted only in rinse-off products, up to 0.0015% (Annex V, entry 57), and so is its mixture with Methylchloroisothiazolinone (Annex V, entry 39).⁶
• Formaldehyde releasers. Since 1 August 2026, every product made available in the EU that contains a preservative releasing formaldehyde must carry the warning releases formaldehyde when the total formaldehyde released exceeds 0.001% (Annex V, preamble, point 2).⁶ The threshold used to be 0.05%; it was lowered because the SCCS found that level did not sufficiently protect people already sensitised to formaldehyde.¹⁰

These notes concern people who are, or may become, allergic to a specific substance. They are not a judgement on a product that lists one, and a preservative's absence says nothing about what replaced it. See cosmetic preservatives for the wider picture.

Alcohol: check which kind

Some people choose products without ethyl alcohol because they believe it dries their skin, the FDA notes. On a label, Alcohol on its own means ethyl alcohol, and denatured alcohol appears as Alcohol Denat. or as SD Alcohol followed by a number. Fatty alcohols such as Cetearyl Alcohol are different substances with quite different effects on the skin, and they can appear even in products labelled alcohol free.¹¹ Alcohol denat. in skincare explains more.

What "for sensitive skin" and "hypoallergenic" mean

In the US there is no federal standard or definition for "hypoallergenic", "fragrance-free" or "for sensitive skin", so the FDA says checking for those words is not enough.² Hypoallergenic means whatever a particular company wants it to mean, and makers do not have to submit evidence for it to the FDA. A 1975 FDA regulation that would have required comparative tests was ruled invalid by a federal appeals court.¹²

EU guidance sets a higher bar, though it is guidance rather than law. Annex IV of the technical document on claims says a product may be called hypoallergenic only if it was designed to minimise its allergenic potential and the company holds robust data confirming a very low allergenic potential. Known allergens should be avoided entirely, including substances classified as skin sensitisers. Even then, the claim does not guarantee a complete absence of allergy risk, and the product should not give that impression.¹³ The same document says "dermatologically tested" implies the product was tested on people under a dermatologist's supervision.¹³

"For sensitive skin" is defined nowhere in the EU cosmetics regulation or that guidance. It is the brand's own description, held only to the general criteria every claim must meet.¹⁴ For more claims like these, see natural, organic and hypoallergenic cosmetics.

What to look for on the label

• Parfum, Aroma or Fragrance, and any fragrance substance named after it.
• Plant oils and extracts that carry scent, including those the EU now names as allergens.
• Preservatives you already know you react to, by their label names, and on EU packs the warning releases formaldehyde.
• Alcohol, Alcohol Denat. or SD Alcohol, if you avoid ethanol, and where it sits in the list. Ingredient list order explains what position can show.
• The claims on the front last: they are the brand's words, not a standard.

A label shows what is in a product, not how your skin will respond to it. If a product makes your skin sting, burn or break out in a rash, speak to a doctor or pharmacist. The FDA notes that sensitivity to allergens can become more severe over time, and that a doctor may recommend patch testing to find the cause.² The ingredient checker marks fragrance, named fragrance allergens and drying alcohol in a list you paste, so you can find the names you already know affect you.