New York State Cosmetology Practice Exam 2026 – The All-in-One Guide to Master Your Certification!

Hair dyes are known to be one of the common salon products that can lead to allergic reactions. This is primarily due to the presence of certain chemicals in hair dye formulations, such as paraphenylenediamine (PPD), which is widely used in darker hair dyes. These chemicals can cause sensitivity in some individuals, leading to allergic reactions that may manifest as itching, redness, swelling, or rashes on the scalp and skin.

For salon professionals, it is crucial to conduct a patch test before applying hair dye to a client's hair. This test helps identify any potential allergic reactions by applying a small amount of the dye to a less visible area, allowing time to observe any adverse reactions. Understanding the risk of allergic reactions to hair dyes helps protect clients and ensures a safer salon environment.

Other products like shampoos, conditioners, and hair sprays may cause skin irritations or allergies, but the incidence is less common compared to hair dyes, which have a higher variation in chemical composition depending on the brand and color used.