N-Butyl Resorcinol (4-n-butylresorcinol) is a resorcinol derivative used in topical formulations to reduce hyperpigmentation by inhibiting tyrosinase and related enzymes involved in melanin synthesis. It is regarded as one of the more potent topical tyrosinase inhibitors and is used for melasma and uneven skin tone.
| Reported effect | How often | Notes |
|---|---|---|
| Mild transient erythema | Common | Temporary redness at the application site, usually mild and self-resolving. |
| Stinging or burning sensation | Uncommon | Brief irritation reported shortly after application, often dose- or concentration-dependent. |
| Dryness or scaling | Uncommon | Localized skin dryness with regular use. |
| Contact dermatitis / allergic sensitization | Rare | Occasional reports of irritant or allergic reactions; patch testing may be advised for sensitive individuals. |
| Post-inflammatory hyperpigmentation | Rare | Paradoxical pigmentation following irritation, more likely in darker skin types. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.