Ingredient compatibility
Methylisothiazolinone + Phenoxyethanol: Are They Compatible?
No label conflict foundInformation from the FDA label and published sources. Not medical advice.
Why
These preservatives function through complementary antimicrobial mechanisms—methylisothiazolinone disrupts microbial protein synthesis while phenoxyethanol compromises cell membrane integrity. They're chemically stable together and often co-formulated at reduced concentrations to achieve broad-spectrum preservation while minimizing individual sensitization risk. Neither compound interferes with the other's preservative efficacy or pH stability.
Usage guidance
This is a standard preservative combination used to lower individual preservative loads in formulations. If you have known contact allergy to methylisothiazolinone specifically, avoid products containing it regardless of co-ingredients, as sensitization persists independently.
Educational content — not medical advice. Always check with your dermatologist for ingredient-specific questions.