It doesn’t work like that because the shampoo isn’t able to dye hair, tint it. What’s more far fewer know of a hack that makes it even more effective. Let’s be honest about blonde hair for a sec. Some parts of your hair may … If you can, squeeze a small amount of the purple shampoo onto your finger before buying it to make sure it has a solid color. Maine likes Color Wow Color Control Toning and Styling Foam as a great alternative to purple shampoo that neutralizes brassiness, and it comes in a purple tone for lighter, blonde hair … For example, they have black or brown hair and believe that the shampoo will leave their hair violet. Some want to use the shampoo on dry hair to dye it. Too many have no idea how to use it right. The purple shampoo bottle will tell you to apply it to wet hair in the shower for 10 minutes, but is to apply it to dry hair and leave it on for upwards of 15 minutes and THEN wash it out. Find a purple shampoo with a thick color and consistency. Can you use the shampoo to dye your hair violet or purple? You c… That’s to use purple shampoo to cancel out unwanted brassiness. A high-quality purple shampoo should be opaque, not transparent, in color.  X Research source Great options include Matrix So Silver purple shampoo and Paul Mitchell Platinum Blonde purple shampoo. They apply and leave it for about 5 minutes and rinse it out. People commonly use a purple shampoo in the shower. How to Apply Purple Shampoo to Your Dry Hair. Keeping it looking pretty, super bright and free from brass is not easy. But there’s a problem. There is an age old fix. However, this shampoo works better when applied on dry hair.