B Block is a combination cosmetic ingredient marketed as a broad-spectrum UV and infrared/visible-light protective system, typically blending organic and/or mineral filters with antioxidants. It is used in sunscreens and daytime moisturizers to reduce UV-induced skin damage.
| Reported effect | How often | Notes |
|---|---|---|
| Mild transient stinging or skin irritation | Uncommon | Often related to organic UV filters or other formulation components; usually self-limiting. |
| Contact dermatitis / allergic sensitization | Rare | Some organic UV filters can act as allergens or photoallergens in susceptible individuals. |
| Eye irritation or watering | Uncommon | Occurs if product migrates into the eyes, particularly with sweating. |
| Acneiform breakouts or follicular occlusion | Rare | More likely in oily/acne-prone skin with heavier emollient bases. |
| White cast or cosmetic residue | Common | A cosmetic rather than medical effect, mainly when mineral filters are included. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.