Vitamin B3 (niacinamide) is a water-soluble vitamin derivative used in skincare to support the skin barrier, regulate sebum, reduce hyperpigmentation, and improve the appearance of fine lines and uneven tone. It is generally well tolerated across a wide range of skin types and concentrations.
| Reported effect | How often | Notes |
|---|---|---|
| Mild transient flushing or warmth | Uncommon | More associated with niacin than niacinamide; usually brief and harmless. |
| Skin irritation, stinging, or redness | Uncommon | More likely at higher concentrations (above ~5%) or on sensitive skin. |
| Allergic contact dermatitis | Rare | Isolated case reports; presents as itching, rash, or swelling. |
| Worsening of rosacea or breakouts | Rare | Occasional reports, often formulation- or concentration-dependent. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.