What symptoms should a barber recognize as an allergic reaction?

Recognizing the symptoms of an allergic reaction is crucial for barbers, as they often work with various chemicals, products, and tools that could cause skin sensitivities. The correct response identifies redness, swelling, and itching as key indicators of an allergic reaction.

Redness, or erythema, typically occurs as a result of inflammation due to the body's immune response to an allergen. Swelling, or edema, is another common symptom, indicating that the body is reacting by increasing blood flow and immune cell activity in the affected area. Itching, or pruritus, often accompanies allergic reactions because the release of histamines and other chemicals from the immune system can irritate nerve endings in the skin.

Together, these symptoms serve as clear signals for barbers to take action, such as discontinuing the use of a product or referring a client to a medical professional for further evaluation. The other options listed describe general skin conditions or irritations that may not necessarily indicate an allergic reaction. Therefore, being able to recognize the combination of redness, swelling, and itching empowers barbers to maintain their clients' safety and comfort.