Allergic reaction
Another possible cause (especially if you are a woman) could be an allergic reaction. For example, if you’ve colored your hair, maybe your scalp itches because you’re having an allergic reaction to the dye. And it doesn’t matter if you’ve used the exact same product before without any issues.
The director of Cosmetic and Clinical Research at Mount Sinai Hospital in New York City and board-certified dermatologist Joshua Zeichner, MD, says that you can experience an allergic reaction even when you’ve used the product several times before without any incident.
In fact, you can have an allergic reaction even from shampoo or a beneficial hair treatment. If you’re more prone to having allergic reactions, a Clinical Instructor at the University of Southern California and board-certified dermatologist in Beverly Hills, Tsippora Shainhouse MD, suggests using one hair product at a time. This way, you’ll find out exactly to which ingredients your scalp is sensitive.
