Tinosorb M (methylene bis-benzotriazolyl tetramethylbutylphenol, also known as bisoctrizole) is a broad-spectrum organic UV filter that absorbs, reflects, and scatters both UVA and UVB radiation. It is a microfine particulate filter that remains stable in formulation and is widely used in sunscreens outside the United States.
| Reported effect | How often | Notes |
|---|---|---|
Skin irritation or mild stinging | Rare | Generally well tolerated; occasional mild irritation reported. |
Allergic contact dermatitis | Very rare | Low sensitizing potential; isolated case reports exist. |
Contact urticaria | Very rare | Rarely reported immediate hypersensitivity reaction. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.