We shampoo, condition and even complete deep-cleansing masks once a week—all to get weightless, gorgeous hair like Blake Lively. We thought that this discipline put us at the peak of our hair care game—until we started noticing pre-shampoos on the shelves. Suddenly, we feel remarkably remiss; what the heck is this stuff and should we be adding it to our AM lineup?
The first thing to know is that pre-shampoos aren't entirely new—often, they function like a traditional scalp treatment. Some exfoliate the scalp while simultaneously hydrating the shafts of the hair; others are geared to reduce scalp irritation and buildup.