Riboflavin (vitamin B2) is a water-soluble vitamin used in skincare for its antioxidant properties and role in supporting skin cell metabolism and barrier function. In topical formulations it may help protect against oxidative stress, though it is also light-sensitive and can act as a photosensitizer.
| Reported effect | How often | Notes |
|---|---|---|
| Mild skin irritation or stinging | Rare | Occasional transient irritation at application site, generally mild. |
| Yellow staining of skin or fabric | Uncommon | Riboflavin has an intense yellow color that may temporarily tint skin or clothing. |
| Photosensitivity / phototoxic reactions | Rare | Riboflavin can generate reactive oxygen species under UV/blue light, theoretically increasing light sensitivity. |
| Allergic contact dermatitis | Very rare | Isolated reports of hypersensitivity reactions. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.