Pr
Propylparaben
Propylparaben
Longer-chain paraben. Permitted in most regions at low concentrations; often paired with methylparaben.
What it does
Propylparaben extends the antifungal coverage that methylparaben provides on the antibacterial side, which is why the two often appear together. Permitted up to 0.14% in the EU. Like methylparaben, the safety record under topical use is strong; the marketing fear is disproportionate to the regulatory consensus.
The evidence, graded
moderateCommon sensitivity and contact-allergy triggers in skincare include fragrance (the most-cited cosmetic allergen), essential oils, denatured alcohol, and certain preservatives (methylisothiazolinone, formaldehyde-releasers). Patch test new products on the inner forearm for 48–72 hours before face-wide use.Warshaw 2020 · Dermatitis ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Pairs worth knowing
Browse all 668 ingredients — grouped by what they do, each with whatever evidence we can cite.
This page is public so a shared ingredient card always has its sources behind it — and so you can check them without an account.
Want more like this?
Every evidence-based flag cites its source, Drop tells you when your routine is complete, and it helps you simplify — instead of selling you more. The app launches on iOS and Android in October 2026. Rate my routine works today at /rate — no sign-in.