Olaplex No.4P Purple Toning Shampoo – Neutralize Brass, Strengthen Hair

Olaplex Nº.4P Blonde Enhancer Purple Toning Shampoo – $25.50 (25% off, was $34.00) · 4.5/5 · 11,750 ratings · 9K+ bought last month Ultra-concentrated purple toning shampoo formulated to neutralize brassiness and yellow tones in blonde, gray, or highlighted hair while repairing damage and hydrating from roots to ends. Works on natural and color-treated hair, for coily, curly, straight, and wavy textures. Apply to wet hair, lather, let sit 1–3 minutes, rinse. 8.5 fl oz. Reviews are strong at 4.5/5 (79% five-star). Users consistently praise how effectively and quickly it neutralizes brassy or yellow tones — several describe dramatic before/after results after a single wash, including correcting green or brassy tints from hard water, and many say it leaves hair soft rather than the straw-like texture some purple shampoos cause. Fair caveats worth flagging: this is a potent toner — leaving it on too long can over-tone hair, shifting blonde toward silver/grey/purple-grey rather than the intended neutral tone, so start with shorter processing times and check progress. A handful of users find it does leave hair feeling dry afterward, with most recommending it be followed by a good conditioner (Olaplex Nº.5P or similar) to restore softness. As with most potent toners, it's best used as an occasional treatment rather than a daily shampoo.