Its not advised to use purple shampoo as your everyday shampoo, it should only be used to eliminate unwanted brassy, yellow tones in the hair on an occasional basis. Overuse of purple toning shampoos can cause the hair to appear dull and darker over time and even become grey/purple. It can also dry the hair out if used continuously so stick to no more than once every two weeks and use a hydrating shampoo in between like the Cliphair Deep Moisture Shampoo.