Anti-yellow shampoo is a hair care product specifically designed to reduce or eliminate unwanted yellow or brassy tones in blonde, gray, or lightened hair. These shampoos work by utilizing the principles of color theory, where complementary colors cancel each other out. In this case, the purple or blue pigments found in the shampoo counteract the yellow tones, resulting in a cooler, more neutral or ashier appearance.

These shampoos are commonly used after hair has been bleached, highlighted, or colored, as the bleaching process can expose underlying warm undertones that give the hair a yellow or orange hue. They contain special ingredients that deposit violet or blue micro-pigments onto the hair shaft as you wash, neutralizing yellow tones and giving the hair a brighter, more refreshed look.

Additionally, some anti-yellow shampoos also feature clarifying properties to remove impurities, build-up, and environmental deposits that can contribute to brassiness. They are typically formulated to be gentle on chemically treated hair to prevent further damage while ensuring that the hair maintains its intended tone.

Regular use of an anti-yellow shampoo, as directed, can help maintain a salon-fresh look between appointments and extend the life of color treatments. However, users must be cautious not to overuse these products, as they can potentially dry out the hair if used excessively.