Pore-clogging ingredients / Isopropyl Isostearate
Is Isopropyl Isostearate comedogenic?
Yes. This is one of the most pore-clogging ingredients on record.
- Comedogenic rating
- 5/5
- Severely comedogenic
- Evidence confidence
- high
- Published lists agree on this rating.
- Also appears as
- No common label aliases
What is Isopropyl Isostearate?
A branched-chain ester used as an emollient and texture enhancer. It spreads easily and leaves a dry, powdery finish, making it common in facial moisturizers, sunscreens, and long-wear makeup.
What to do if you're acne-prone
Avoid it in any product if you're acne-prone, including rinse-off products and haircare that touches your face. At this rating, concentration rarely saves a formula.
Where this rating comes from
Our ratings consolidate two lineages: the original rabbit-ear comedogenicity assays published by James Fulton and colleagues (Fulton, Pay & Fulton, Journal of the American Academy of Dermatology, 1984; Fulton, Journal of the Society of Cosmetic Chemists, 1989), and the pore-clogger lists maintained by acne-specialist estheticians in the Face Reality lineage that refine those assays with decades of client observation. Both source lineages agree on this ingredient's rating.
Last reviewed 2026-08-15 by the PorePass editorial team.
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Comedogenicity ratings come from published ingredient studies and esthetician-compiled lists. They are imperfect and formulation-dependent, and this page isn't medical advice. Reactions vary by skin, concentration, and the rest of the formula.