Niacin is a form of vitamin B3 that supports cellular energy metabolism and skin barrier function; in topical skincare it is often used interchangeably with or converted to niacinamide. It may improve skin hydration and tone when formulated appropriately.
| Reported effect | How often | Notes |
|---|---|---|
| Transient flushing/redness | Common | Niacin (nicotinic acid) can trigger vasodilation and a warm, red sensation, more so than niacinamide. |
| Mild stinging or tingling | Uncommon | Usually temporary and concentration-dependent. |
| Itching or irritation | Uncommon | More likely on sensitive or compromised skin. |
| Contact dermatitis | Rare | Allergic or irritant reactions reported in isolated cases. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.