TIGI Bed Head Cleansing Purple Shampoo, 13.5-Ounce

Whether you were born with blonde hair or you pay for it, it can be tough to get the color just right. Even if it looks perfect the day you color it, it can gradually lose its luster and start to turn brassy. Those yellows, oranges and reds that make blonde hair look less brilliant than you’d prefer are hard to avoid.

Stylists typically add a toner to reduce those colors, known as undertones. But not everyone pays for salon color and, of those who do, the toner can lose its power over time. That means in the weeks following your appointment, you may find that your blonde takes on a bit of brassiness, which you’re stuck with until your next coloring.

That’s where purple shampoo comes in. If you look at a color wheel, purple is directly across from yellow, and colors located on opposing sides of the wheel cancel each other out. When purple is applied to your hair, it cancels out the yellow tones, providing that icy blonde color that is seen as the ideal.

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But blonde hair isn’t the only hair color that can benefit from a tube of purple shampoo. Those with silver hair also find undertones starting to appear, and purple shampoo can help with that, as well. Some with dramatic blonde or silver highlights also find that purple shampoo provides better color, although it has no effect on other hair colors.

• You don’t have to have dyed hair to benefit from purple shampoo. In fact, those with naturally blonde and naturally silver hair find it reduces undertones.
• Purple shampoo can dry out your hair. Look for one that is formulated to overcome that obstacle, leaving your hair soft, shiny and undertone free.
• For those with damaged or dry hair, a nourishing toning mask will probably be better for your hair than a purple shampoo.
• Just because you use purple shampoo, doesn’t mean you can do away with a toner. If your salon provides that service, use purple shampoo as a supplement. If you color your own hair, look for a toner that can reduce undertones.
• Don’t use purple shampoo in the first two weeks after your hair has been colored. The hair is more porous following bleaching, making it more likely you’ll get blotchy, uneven results.
• Follow the instructions closely on the bottle. If a time range is recommended for leaving the shampoo on your hair, go with the low end of that range at first, then increase as you get more comfortable with the results. Leaving purple shampoo on too long can create a lavender hue, although some like having that tint and choose to leave it on longer to get there.