It is possible to wash food coloring out of an individual's hair, but it may take multiple washes and treatments before all of the color is removed. For easier removal, clarifying shampoo and hair developer can be combined to cleanse the hair.
Mix equal parts clarifying shampoo and hair developer together. After an individual washes his or her hair with just the clarifying shampoo, apply the mixture thickly to all of the hair. After 5 minutes has passed, rinse it out, and the color should be gone. If any color remains, use the hair developer and clarifying shampoo mixture again. Once all of the food color is removed, treat the hair with conditioner.