Basic Red 51
Basic Red 51 is a synthetic organic dye used in hair coloring products. It is responsible for creating red and reddish-pink tones in hair, particularly in semi-permanent and temporary dye formulations. This ingredient works by depositing color molecules onto the hair shaft.
Hair dyeVegan
RiskModerate 1.5 / 4
Sensitization i1.5 / 4
Risk of allergic contact dermatitis or immune-based reactions. Fragrance allergens, preservatives, botanicals, and some dyes may score here.
Irritation i1.5 / 4
Risk of short-term irritation — stinging, burning, dryness, redness, or discomfort. Common for strong actives, acids, retinoids, fragrances, and harsh surfactants.
Rated by SpottyLabs' ingredient methodology, independent of brands.
Things to watch
- Potential for skin irritation
- Can cause allergic reactions
- May stain skin and clothing
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Frequently asked questions
- What is Basic Red 51 used for?
- Basic Red 51 is a synthetic dye primarily used in hair coloring products to create red and reddish-pink shades. It is often found in semi-permanent or temporary hair dyes.
- Is Basic Red 51 safe for all hair types?
- While generally considered safe for use in hair products, some individuals may experience skin irritation or allergic reactions. A patch test is recommended before full application.
