PoriMethylisothiazolinone at a glance
| Function | Preservative |
|---|---|
| Comedogenic rating | 0/5 |
| Irritation potential | High |
| Also listed as | MIT |
| How common | On 880 of 21,918 product labels in Pori's copy of Open Beauty Facts |
Is Methylisothiazolinone good for my skin type?
These ratings come from the same fixed rules Pori's ingredient scanner uses, applied to a typical profile for each skin type. Your own result in the app also weighs your scan results and concerns.
| Skin type | Rating | Why |
|---|---|---|
| Normal | Avoid | Frequent cause of contact allergy; banned in EU leave-on products. |
| Dry | Avoid | Frequent cause of contact allergy; banned in EU leave-on products. |
| Oily | Avoid | Frequent cause of contact allergy; banned in EU leave-on products. |
| Combination | Avoid | Frequent cause of contact allergy; banned in EU leave-on products. |
| Sensitive | Avoid | Frequent cause of contact allergy; banned in EU leave-on products. |
What should I watch for?
- Known sensitizer: a frequent cause of contact allergy, even on skin that isn't usually sensitive.
Is Methylisothiazolinone comedogenic?
It has a comedogenic rating of 0 out of 5 in Pori's ingredient database, so it's unlikely to clog pores. Ratings like this come from older tests on single ingredients, and a finished product with it isn't necessarily pore-clogging. A 2006 study in the Journal of the American Academy of Dermatology found that finished products made with comedogenic ingredients were not necessarily comedogenic, so treat the number as a hint, not a verdict.
How do I check a product with Methylisothiazolinone?
Scan the barcode or photograph the ingredient list with Pori's ingredient scanner (a Pro feature). It rates every ingredient for your skin type, flags fragrance, pore-clogging and irritating ingredients, and gives the product an overall match score. It's a guide to ingredients, not a diagnosis, so see a dermatologist about any reaction.
Keep reading
- Best Skincare Ingredient Checker Apps in 2026: Pori, SkinSort, INCIDecoder, Yuka and More
- How to Read Skincare Ingredient Labels: INCI Lists, Fragrance and What to Avoid
- Skincare Ingredients Not to Mix: Real Conflicts vs Myths
Ingredient data from Pori's ingredient database; product counts from Open Beauty Facts (ODbL). General information, not medical advice.