What is a common symptom of an allergic reaction to hair dye?

A common symptom of an allergic reaction to hair dye is the presence of redness, swelling, or rash on the skin. When a person is allergic to certain ingredients found in hair dye, their immune system reacts and triggers an inflammatory response in the skin. This results in symptoms such as localized redness, swelling, and sometimes a rash or hives where the dye was applied or came into contact with the skin. Recognizing these symptoms is crucial for both the stylist and the client to ensure safety and to take appropriate action, such as removal of the product and seeking medical treatment if necessary.

The other symptoms listed, such as extreme dryness and brittleness of hair, uneven hair texture and breakage, or lack of shine or color vibrancy, are more indicative of hair damage due to chemical processes or environmental factors rather than an allergic reaction. These can occur from improper application techniques or using products that are too harsh for the hair but do not involve the body's immune response in the way that allergic reactions do.