Answer:
I’m not a cosmetologist but i do have a lot of experience with hair. Yes, purple shampoo can be used after a balayage if you’d like to counteract some of the brassy tones. Although, you should wait 48-72 hours after you get it done to wash it. Otherwise, you’d be wasting good money from that balayage :)).
Step-by-step explanation:
hope i helped :)).