COSRX The Niacinamide 15 Serum vs The Ordinary Niacinamide 10% + Zinc 1%
COSRX
The Niacinamide 15 Serum
~$18· 20ml
NiacinamideSodium PCA
The Ordinary
Niacinamide 10% + Zinc 1%
~$6· 30 ml
Niacinamide
Actives breakdown
| Active ingredient | COSRX | The Ordinary |
|---|---|---|
| Niacinamide | ✓ | ✓ |
| Sodium PCA | ✓ | — |
Layering & Safety
Combined Verdict
Safe to layer
No layering conflicts flagged between these two. Patch-test new actives as usual.