Georgia Barber License Practice Exam 2026 – Comprehensive All-in-One Guide to Pass with Confidence!

Paraphenylenediamine (PPD) is commonly linked to allergic reactions in hair color formulations. It is a dye intermediate found in many permanent hair dyes and has a well-documented history of causing sensitivity and allergic responses in some individuals. When applied to the hair, PPD can penetrate the skin and trigger reactions ranging from mild irritation to severe allergic dermatitis, especially in those who have developed a sensitivity to it over time.

In contrast, while ammonia and hydrogen peroxide are essential components of hair dye formulations and can cause irritation or other reactions, they are typically not the primary allergens associated with hair color. Glycolic acid, often used in skin care and hair removal products, does not have the same level of association with hair dye allergies as PPD does. Therefore, when considering the common causes of allergic reactions specifically in the context of hair coloring, PPD stands out as the key ingredient responsible for such reactions.