Ingredient dictionary

Alpha-Isomethyl Ionone

A synthetic fragrance ingredient with a soft floral, violet-like scent. Its main job is to give a product its fragrance. It is on the label of 112 products in our library. Checked against our library November 6, 2026.

The catch: it is one of the 26 fragrance allergens the EU requires brands to name on labels, because it can cause skin reactions in some people. Check the label if you know you react to it.

Labelled fragrance allergens. If you know you react to one of them, this is the line to check. They also show up in products scented only with essential oils.

What Alpha-Isomethyl Ionone does

Gives products a soft, violet-like scent
Adds floral depth to fragrance blends
Rounds out other scent notes

Alpha-Isomethyl Ionone is a synthetic scent made in a lab from related fragrance building blocks. It belongs to the ionone family, a group of chemicals known for their violet-like aromas.

Formulators use it to add a soft floral note to shampoos, lotions and deodorants, often blended with other scents. It is a liquid that mixes easily into fragrance oils, and it is usually used in small amounts so the scent stays balanced.

Good for

Suits people who like soft floral scents and have no known reaction to fragrance ingredients.

Be careful if

It is one of the 26 fragrance allergens the EU requires brands to name on labels, because it can cause skin reactions in some people. Check the label if you know you react to it.

Frequently asked questions

Is Alpha-Isomethyl Ionone safe for sensitive skin?

Many people with sensitive skin use products containing it without problems, but it is a known fragrance allergen. If your skin reacts to fragrance, look for it on the label and consider a fragrance-free product. A patch test on a small area is a sensible first step.

Is it the same as natural violet or orris scent?

No. It is made in a lab to smell like violet. Plant-based violet and orris extracts contain many aromatic compounds at once, so they are more complex.