Nit (niacinamide) is a water-soluble form of vitamin B3 used in skincare to support the skin barrier, regulate sebum, and reduce hyperpigmentation and redness. It is generally well tolerated across a range of skin types and is commonly combined with other actives.
| Reported effect | How often | Notes |
|---|---|---|
Mild transient flushing or warmth | Uncommon | More likely at higher concentrations; usually brief and self-resolving. |
Tingling, stinging, or itching | Uncommon | Typically on application, especially on sensitive or compromised skin. |
Redness or irritation | Rare | More common at high concentrations (above ~5-10%) or with frequent use. |
Allergic contact dermatitis | Very rare | Isolated case reports; patch testing advised if suspected. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.