*Contact dermatitis*
Dr. Chacon also mentions contact dermatitis, an  allergic reaction or irritation related to  hair products, especially hair dye or shampoo. “Read product labels and know what to look for,” warns Dr. Anna Chacon. She specifically points out sulfates, parabens, alcohol, fragrances, and synthetic dyes, substances that can cause itching, especially if you already have sensitive skin or already have a scalp  skin condition.

“If you notice any of the ingredients listed above, especially among the first ones mentioned on the label (which indicates a higher concentration), you might want to consider alternative products. For people with sensitive skin or prone to scalp irritation, choose products labeled hypoallergenic, for sensitive skin, or completely natural,” recommends the specialist, who advises doing a skin patch test before using a hair product for the first time: apply the product to the inner part of your forearm and leave it on for a full day. If you feel irritation or itching in that area, you should not use the product.

*Lice, eczema, hives: other conditions that can cause itching*
To complete the list of that can be responsible for scalp itching, an article published in Harvard Health Publishing, the Harvard Medical School site, also mentions atopic dermatitis, a form of eczema that can also affect the scalp. You also shouldn’t rule out the possibility of a fungal infection, lice, or hives that can appear as a reaction to food, medication, sweat… If your itching is due to this type of condition, you’ll need a medical prescription to adopt an effective treatment.