Ingredient glossary
Methylisothiazolinone
INCI: Methylisothiazolinone · Also: MI
Quietly necessary
Does Methylisothiazolinone clash with what you already use? Check it →A preservative doing an unglamorous but essential job: keeping the product safe to use. Not something you pay extra for.
What it does
- preservation
strong evidenceEpidemiologic data from large patch-test series show methylisothiazolinone sensitization rates reaching six to seven percent with facial and hand dermatitis from cosmetics and paints prompting regulatory restriction.
Who it's for, and who should skip it
Tends to suit
- all
Approach with care
- very sensitive
- eczema
- formaldehyde allergy
- Clogs poresLow
- Irritation riskHigh
Plays well with
- alternative preservatives
This, for every label you own
One ingredient is easy. A full label is where it gets confusing. The Ingredient Decoder reads any product and tells you the honest truth, ingredient by ingredient.
Educational information about a cosmetic ingredient, not medical advice.