Cosmetology Practice Test – Pass the Massachusetts State Board Exam (2025 Guide)

Itching or swelling is a common symptom of an allergic reaction to hair color because these reactions typically involve the body's immune system responding to certain chemicals present in the dye, such as para-phenylenediamine (PPD). When someone is allergic to an ingredient in hair color, the skin may exhibit localized symptoms such as redness, itching, and swelling where the product has been applied.

This kind of response is often seen as part of a condition called contact dermatitis, where the skin reacts to irritants or allergens with inflammation. It's important for cosmetologists to conduct patch tests prior to applying hair color to determine if a client may have an allergic reaction, thereby minimizing the risk of discomfort or serious health issues for the client. Other choices, while they might relate to different health concerns or reactions, do not specifically align with the typical symptoms experienced during an allergic response to hair color.